0001039399-23-000010 | 10-K | XBRL Viewer

Derivative Financial Instruments

12 Months Ended

Dec. 31, 2022

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Foreign Exchange Derivative Contracts

We operate and sell our products in various global markets. As a result, we are exposed to changes in foreign currency exchange rates. We utilize foreign currency forward contracts to hedge against future movements in foreign exchange rates that affect certain existing foreign currency denominated assets and liabilities and forecasted foreign currency revenue and expense transactions. Under this program, our strategy is to have increases or decreases in our foreign currency exposures mitigated by gains or losses on the foreign currency forward contracts in order to mitigate the risks and volatility associated with foreign currency transaction gains or losses.

We do not use derivative financial instruments for speculative or trading purposes. For accounting purposes, certain of our foreign currency forward contracts are not designated as hedging instruments and, accordingly, we record the fair value of these contracts as of the end of our reporting period in our Consolidated Balance Sheets with changes in fair value recorded within Other income, net in our Consolidated Statements of Income for both realized and unrealized gains and losses. Certain of our foreign currency forward contracts are designated as cash flow hedges, and, accordingly, we record the fair value of these contracts as of the end of our reporting period in our Consolidated Balance Sheets with changes in fair value recorded as a component of Accumulated other comprehensive loss and reclassified into earnings in the same period in which the hedged transaction affects earnings, and in the same line item on the Consolidated Statements of Income as the impact of the hedge transaction. At December 31, 2022, we expect to reclassify $0.5 million of the amount accumulated in other comprehensive loss to earnings during the next 12 months, due to the recognition in earnings of the hedged forecasted transactions.

The fair value of our foreign exchange derivative contracts was determined based on current foreign currency exchange rates and forward points. All of our foreign exchange derivative contracts outstanding at December 31, 2022 will mature by the fourth quarter of fiscal 2023.

The following table provides information about our foreign currency forward contracts outstanding as of December 31, 2022 (in thousands):


Currency	Contract Position	Contract Amount (Local Currency)	Contract Amount (U.S. Dollars)
Euro	Buy	21,576	$	22,615
Euro	Sell	4,927	5,107
Japanese Yen	Sell	2,989,654	22,906
Korean Won	Buy	2,067,724	1,639
Taiwan Dollar	Sell	42,826	1,397

Our foreign currency contracts are classified within Level 2 of the fair value hierarchy as they are valued using pricing models that utilize observable market inputs.

The location and amount of gains (losses) related to non-designated derivative instruments in the Consolidated Statements of Income were as follows (in thousands):


	Location of Gain (Loss) Recognized on Derivatives	Fiscal Year Ended
Derivatives Not Designated as Hedging Instruments		December 31, 2022		December 25, 2021		December 26, 2020
Foreign exchange forward contracts	Other income, net	$	2,439	$	1,585	$	(1,437)

The location and amount of gains (losses) related to foreign currency derivative instruments designated as cash flow hedges on our Consolidated Statements of Income was as follows (in thousands):


	Amount of Gain or (Loss) Recognized in Accumulated OCI/L on Derivative		Location of Gain or (Loss) Reclassified from Accumulated OCI/L into Income	Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income
Fiscal 2022	$	(1,688)	Cost of revenues	$	(1,816)
			Research and development	(376)
			Selling, general and administrative	(456)
				$	(2,648)

Fiscal 2021	$	(1,096)	Cost of revenues	$	184
			Research and development	3
			Selling, general and administrative	64
				$	251

Fiscal 2020	$	1,142	Cost of revenues	$	89
			Research and development	77
			Selling, general and administrative	25
				$	191

Interest Rate Swaps

During fiscal 2020 we entered into an interest rate swap agreement with Union Bank to hedge the interest payments on the Building Term Loan for the notional amount of $18.0 million. As future levels of LIBOR over the life of the loan are uncertain, we entered into this interest-rate swap agreement to hedge the exposure in interest rate risks associated with movement in LIBOR rates. By entering into the agreement, we convert a floating rate interest at one-month LIBOR plus 1.75% into a fixed rate interest at 2.75%. The interest rate swap also included a 0% floor that was effective for one year from the date of the swap. As of December 31, 2022, the notional amount of the loan that is subject to this interest rate swap was $15.5 million. See Note 5, Debt, for additional information.

For accounting purposes, the interest-rate swap contracts qualify for and are designated as cash flow hedges. All hedging relationships are formally documented, and the hedges are designed to offset changes to future cash flows on hedged transactions. We evaluate hedge effectiveness at hedge inception and on an ongoing basis.

The fair value of our interest rate swap contracts are determined at the end of each reporting period based on valuation models that use interest rate yield curves as inputs. The cash flows associated with the interest rate swaps are reported in Net cash provided by operating activities in our Consolidated Statements of Cash Flows and the fair value of the interest rate swap contracts are recorded within Prepaid expenses and other current assets and Other assets.

The impact of the interest rate swaps on the Consolidated Statements of Income was as follows (in thousands):


	Amount of Gain or (Loss) Recognized in OCI/L on Derivative (Effective Portion)		Location of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)	Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)
Fiscal 2022	$	1,906	Other income, net	$	106
Fiscal 2021	451		Other income, net	(154)
Fiscal 2020	(119)		Other income, net	(64)

New Accounting Pronouncements	12 Months Ended
Dec. 31, 2022
Accounting Policies [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements ASU 2021-08 In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers. The new guidance requires contract assets and contract liabilities acquired in a business combination to be recognized and measured by the acquirer on the acquisition date in accordance with Accounting Standards Codification 606, “Revenue from Contracts with Customers,” as if it had originated the contracts. The Company elected to early adopt on a prospective basis during the second quarter of fiscal 2022. The adoption did not have a material effect on the Company's Consolidated Financial Statements.

Income Taxes - Tax Credits and Carryforwards (Details) $ in Thousands	Dec. 31, 2022 USD ($)
California
Operating Loss Carryforwards [Line Items]
California research credits	$ 52,131
Singapore
Operating Loss Carryforwards [Line Items]
Singapore net operating loss carryforwards	5,724
Federal
Operating Loss Carryforwards [Line Items]
Federal research and development tax credit	26,424
Foreign tax credit carryforwards	995
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 249,087

Segments and Geographic Information - Operating Results By Segment (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) segment	Dec. 25, 2021 USD ($)	Dec. 26, 2020 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment	2
Segment Reporting Information [Line Items]
Revenues	$ 747,937	$ 769,674	$ 693,616
Gross profit	$ 296,009	$ 322,767	$ 287,920
Gross margin	39.60%	41.90%	41.50%
Probe Cards
Segment Reporting Information [Line Items]
Revenues	$ 591,422	$ 633,281	$ 581,739
Systems
Segment Reporting Information [Line Items]
Revenues	156,515	136,393	111,877
Operating Segments \| Probe Cards
Segment Reporting Information [Line Items]
Revenues	591,422	633,281	581,739
Gross profit	$ 235,562	$ 279,873	$ 263,215
Gross margin	39.80%	44.20%	45.20%
Operating Segments \| Systems
Segment Reporting Information [Line Items]
Revenues	$ 156,515	$ 136,393	$ 111,877
Gross profit	$ 80,937	$ 65,834	$ 51,835
Gross margin	51.70%	48.30%	46.30%
Corporate and Other
Segment Reporting Information [Line Items]
Revenues	$ 0	$ 0	$ 0
Gross profit	$ (20,490)	$ (22,940)	$ (27,130)

See also Note 9, Fair Value.

Inventories, net

Inventories consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Raw materials	$	55,726	$	57,673
Work-in-progress	46,067		35,935
Finished goods	21,364		17,940
	$	123,157	$	111,548

Property, Plant and Equipment, net

Property, plant and equipment, net consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Land	$	17,136	$	4,751
Building and building improvements	44,932		41,722
Machinery and equipment	276,180		252,632
Computer equipment and software	45,813		44,667
Furniture and fixtures	7,540		7,293
Leasehold improvements	86,500		82,266
Sub-total	478,101		433,331
Less: Accumulated depreciation and amortization	(335,711)		(312,700)
Net property, plant and equipment	142,390		120,631
Construction-in-progress	47,458		25,924
Total	$	189,848	$	146,555

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Accrued compensation and benefits	$	15,864	$	29,706
Accrued income and other taxes	12,817		8,086
Accrued employee stock purchase plan contributions withheld	4,585		4,693
Accrued warranty	4,199		2,805
Accrued restructuring charges	1,249		2,478

Other accrued expenses	3,401		3,068
	$	42,115	$	50,836

Restructuring Charges - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended		15 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 31, 2022
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 15,586	$ 5,621
2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Workforce reduction (percent)	13.00%
Restructuring charges	$ 7,000
2022 Restructuring Plan \| Corporate and Other
Restructuring Cost and Reserve [Line Items]
Restructuring charges	500
2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	8,500		$ 12,600
Probe Cards \| 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	6,000
Probe Cards \| 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges			9,900
Systems \| 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	500
Systems \| 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges			2,700
Employee Severance and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	7,269	1,175
Employee Severance and Benefits \| 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	300		1,300
Contract Termination & Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	502	2,800
Contract Termination & Other Costs \| 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	400		1,800
Inventory Impairments & Other Inventory Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	7,629	$ 1,376
Inventory Impairments & Other Inventory Related Costs \| 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	7,600		9,000
Other Restructuring \| 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	200		500
Minimum \| 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost	8,500		8,500
Maximum \| 2022 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost	$ 9,500		$ 9,500

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit, beginning balance	$ 35,745	$ 32,497	$ 28,800
Additions based on tax positions related to the current year	3,868	3,201	3,072
Additions based on tax positions from prior years	795	124	702
Reductions for tax positions of prior years	0	0	0
Reductions due to lapse of the applicable statute of limitations	(310)	(77)	(77)
Unrecognized tax benefit, ending balance	40,098	35,745	32,497
Interest and penalties recognized as a component of provision for income taxes	30	40	50
Interest and penalties accrued at period end	85	$ 188	$ 204
Tax-effected unrecognized tax benefits	$ 20,200

Income Taxes - Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Income Tax Reconciliation
U.S. statutory federal tax rate	$ 12,153	$ 20,685	$ 17,887
State taxes and credits, net of federal benefit	16	811	663
Stock-based compensation	(2,772)	(6,118)	(4,962)
Research and development credits	(8,264)	(7,153)	(6,576)
Foreign taxes at rates different than the U.S.	2,404	2,286	415
Other permanent differences	1,964	2,043	400
Global intangible low-taxed income	7	0	0
Foreign derived intangible income	(5,160)	(2,486)	(3,668)
Change in valuation allowance	2,597	2,231	1,862
Tax contingencies, net of reversals	3,124	2,812	2,712
Other	1,063	(535)	(2,081)
Total provision for income taxes	$ 7,132	$ 14,576	$ 6,652

Debt

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Debt

Our debt consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Term loans	$	15,499	$	24,435
Less unamortized issuance costs	(65)		(70)
Term loans less issuance costs	$	15,434	$	24,365

FRT Term Loan

On October 25, 2019, we entered into a euro denominated $23.4 million three-year credit facility loan agreement (the “FRT Term Loan”) with HSBC Trinkaus & Burkhardt AG, Germany, to fund the acquisition of FRT GmbH, which we acquired on October 9, 2019.

The FRT Term Loan bore interest at a rate equal to the Euro Interbank Offered Rate (“EURIBOR”) plus 1.75 % per annum and was repaid in quarterly installments of approximately $2.0 million plus interest. We made the final payment on the FRT Term Loan on October 25, 2022. We are no longer subject to the terms of the FRT Term Loan.

Building Term Loan

On June 22, 2020, we entered into an $18.0 million 15-year credit facility loan agreement (the “Building Term Loan”) with MUFG Union Bank, National Association (“Union Bank”). The proceeds of the Building Term Loan were used to purchase a building adjacent to our leased facilities in Livermore, California.

The Building Term Loan bears interest at a rate equal to the applicable LIBOR rate plus 1.75% per annum. Interest payments are payable in monthly installments over a fifteen-year period. The interest rate at December 31, 2022 was 5.87%.

On March 17, 2020, we entered into an interest rate swap agreement with Union Bank to hedge the interest payments on the Building Term Loan for the notional amount of $18.0 million. As future levels of LIBOR over the life of the loan are uncertain, we entered into this interest-rate swap agreement to hedge the exposure in interest rate risks associated with movement in LIBOR rates. By entering into the agreement, we convert a floating rate interest at one-month LIBOR plus 1.75% into a fixed rate interest at 2.75%. The interest rate swap included a 0% floor that was effective for one year from the date of the swap. As of December 31, 2022, the notional amount of the loan that is subject to this interest rate swap is $15.5 million. See Note 9, Fair Value, for additional information.

The obligations under the Building Term Loan are guaranteed by a deed of trust covering certain real property and improvements and certain personal property used in connection therewith. The deed of trust creates a first priority lien or encumbrance on the property with only such exceptions as may be approved by Union Bank in writing.

The Building Term Loan contains covenants customary for financing of this type. As of December 31, 2022, the balance outstanding pursuant to the Building Term Loan was $15.5 million.

Future principal and interest payments on our term loans as of December 31, 2022, based on the interest rate in effect at that date were as follows (in thousands):


	Payments Due In Fiscal Year
	2023		2024		2025		2026		2027		2028 and thereafter		Total
Term loans - principal payments	$	1,050	$	1,080	$	1,111	$	1,142	$	1,175	$	9,941	$	15,499
Term loans - interest payments(1)	894		835		763		699		630		2,324		6,145
	$	1,944	$	1,915	$	1,874	$	1,841	$	1,805	$	12,265	$	21,644

(1) Represents our minimum interest payment commitment at 5.87% per annum for the Building Term Loan, excluding the interest rate swap described above.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (SX 210.4-08(c))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Acquisition - Intangible Assets Acquired (Details) - USD ($) $ in Thousands	Jun. 09, 2022	Jul. 30, 2020	Oct. 09, 2019	Oct. 19, 2020
Woburn
Business Acquisition [Line Items]
Intangible assets	$ 500
High Precision Devices, Inc.
Business Acquisition [Line Items]
Intangible assets			$ 11,520	$ 11,520
Weighted average useful life (in years)			8 years 2 months 12 days
Baldwin Park
Business Acquisition [Line Items]
Intangible assets		$ 13,600
Weighted average useful life (in years)		7 years 8 months 12 days
Baldwin Park \| In-process research and development
Business Acquisition [Line Items]
Intangible assets		$ 400
Developed technologies \| Woburn
Business Acquisition [Line Items]
Weighted average useful life (in years)	3 years
Developed technologies \| High Precision Devices, Inc.
Business Acquisition [Line Items]
Intangible assets			$ 7,500
Weighted average useful life (in years)			10 years
Developed technologies \| Baldwin Park
Business Acquisition [Line Items]
Intangible assets		$ 8,800
Weighted average useful life (in years)		10 years
Customer relationships \| High Precision Devices, Inc.
Business Acquisition [Line Items]
Intangible assets			$ 3,600
Weighted average useful life (in years)			5 years
Customer relationships \| Baldwin Park
Business Acquisition [Line Items]
Intangible assets		$ 4,400
Weighted average useful life (in years)		3 years
Order backlog \| High Precision Devices, Inc.
Business Acquisition [Line Items]
Intangible assets			$ 200
Weighted average useful life (in years)			6 months
Trade name \| High Precision Devices, Inc.
Business Acquisition [Line Items]
Intangible assets			$ 220
Weighted average useful life (in years)			5 years

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsIn January 2023. we received $18.0 million in cash from a California competes grant (the “Grant”) awarded from the California Governor’s Office of Business and Economic Development. The Grant requires FormFactor to create and maintain full-time jobs and make significant infrastructure investments within California over a 5-year term. If we do not meet the requirements of the Grant, we will be required to repay all or a portion of the Grant.

Summary of Significant Accounting Policies - Revenue Remaining Performance Obligation (Details)	Dec. 31, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-12-26
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, percentage	85.70%
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, percentage	9.60%
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-12-31
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, percentage	4.70%
Revenue, remaining performance obligation, expected timing of satisfaction, period

Stock-Based Compensation

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

Stock-Based Compensation Expense

Certain information regarding our stock-based compensation was as follows (in thousands, except per share amounts):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020

Weighted average grant date per share fair value of RSUs granted	$	34.83	$	36.12	$	25.96
Total intrinsic value of stock options exercised	—		3,179		4,688
Fair value of RSUs vested	42,324		54,948		42,597

Pre-tax stock-based compensation expense by financial statement line and related tax benefit in the Consolidated Statements of Income are as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Stock-based compensation expense included in:
Cost of revenues	$	3,807	$	5,200	$	3,951
Research and development	8,217		7,583		5,824
Selling, general and administrative	19,313		16,601		14,055

Total stock-based compensation	$	31,337	$	29,384	$	23,830
Stock-based compensation tax benefit	$	2,772	$	6,118	$	4,962

Unrecognized Stock-Based Compensation Expense

Unrecognized stock-based compensation expense at December 31, 2022 consisted of the following (in thousands):


	Unrecognized Expense		Weighted Average Recognition Period (Years)

Restricted stock units	$	45,726	2.1
Performance restricted stock units	12,216		2.0
Employee stock purchase plan	424		0.1
Total unrecognized stock-based compensation expense	$	58,366	2.1

Valuation Assumptions

The following assumptions were used in estimating the fair value of PRSUs:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
PRSUs:
Dividend yield	—	%	—	%	—	%
Expected volatility	53.0	%	52.5	%	52.0	%
Risk-free interest rate	2.8	%	0.3	%	0.2	%
Expected life (in years)	2.9		2.9		2.8

The following assumptions were used in estimating the fair value of shares under the Employee Stock Purchase Plan:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Employee Stock Purchase Plan:
Dividend yield	—	%	—	%	—	%
Expected volatility	42.6% - 60.8%		33.6% - 74.4%		30.4% - 74.4%
Risk-free interest rate	0.1% - 3.0%		0.1% - 1.5%		0.1% - 1.5%
Expected life (in years)	0.5 - 1.0		0.5 - 1.0		0.5 - 1.0

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 50,738	$ 83,924	$ 78,523
Other comprehensive income (loss), net of tax:
Translation adjustments	(4,864)	(5,995)	5,131
Unrealized gains (losses) on available-for-sale marketable securities	(2,025)	(598)	226
Unrealized gains (losses) on derivative instruments	2,760	(742)	1,188
Other comprehensive income (loss), net of tax	(4,129)	(7,335)	6,545
Comprehensive income	$ 46,609	$ 76,589	$ 85,068

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Stockholders' Equity - Preferred Stock (Details) - $ / shares	Dec. 31, 2022	Dec. 25, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock authorized (in shares)	10,000,000	10,000,000
Preferred stock par value (in USD per share)	$ 0.001	$ 0.001
Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock authorized (in shares)	10,000,000
Preferred stock par value (in USD per share)	$ 0.001

Goodwill and Intangible Assets - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Impairment of intangible assets	$ 0	$ 0	$ 0

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2022
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit PlansWe have an employee savings plan that qualifies as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. The plan is designed to provide employees with an accumulation of funds for retirement on a tax-deferred basis and provide for annual discretionary employer contributions. The total charge to net income under the 401(k) plan for fiscal 2022, 2021 and 2020 aggregated to $2.7 million, $2.7 million and $2.2 million, respectively.

Summary of Significant Accounting Policies - Revenue Recognition (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) distributionChannels	Dec. 25, 2021 USD ($)
Disaggregation of Revenue [Line Items]
Number of distribution channels \| distributionChannels	2
Remaining performance obligations	$ 7.5
Contract assets	1.9	$ 0.9
Contract liabilities	30.9	$ 24.2
Revenue recognized on contract liabilities	$ 20.1
Minimum
Disaggregation of Revenue [Line Items]
Revenue, performance obligation, description of timing	one
Maximum
Disaggregation of Revenue [Line Items]
Revenue, performance obligation, description of timing	three years

Derivative Financial Instruments - Gains (Losses) Of Cash Flow Hedges (Details) - Foreign Exchange Forward - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Foreign exchange forward contracts	$ 2,439	$ 1,585	$ (1,437)
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Amount of Gain or (Loss) Recognized in OCI/L on Derivative (Effective Portion)	(1,688)	(1,096)	1,142
Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)	(2,648)	251	191
Designated as Hedging Instrument \| Cost of revenues
Derivatives, Fair Value [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)	(1,816)	184	89
Designated as Hedging Instrument \| Research and development
Derivatives, Fair Value [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)	(376)	3	77
Designated as Hedging Instrument \| Selling, general and administrative
Derivatives, Fair Value [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)	$ (456)	$ 64	$ 25

Restructuring Charges (Tables)

12 Months Ended

Dec. 31, 2022

Restructuring and Related Activities [Abstract]

Restructuring Costs by Reportable Segment

Total restructuring charges included in our Consolidated Statements of Income for both the 2022 and 2021 Restructuring Plans were as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021
Cost of revenues	$	11,775	$	3,205
Research and development	1,498		869
Selling, general and administrative	2,166		50
	$	15,439	$	4,124

Schedule of Restructuring Accrual Activity

Changes to the restructuring accrual during the years ended December 25, 2021 and December 31, 2022 were as follows (in thousands):


	Employee Severance and Benefits		Inventory Impairments & Other Inventory Related Costs		Property and Equipment Impairments & Other Asset Related Costs		Contract Termination & Other Costs		Total
December 26, 2020	$	—	$	—	$	—	$	—	$	—
Restructuring charges	1,175		1,376		270		2,800		5,621

Adjustment to restructuring charges	(147)		—		—		(1,350)		(1,497)
Non-cash settlement	—		(1,376)		(270)		—		(1,646)
December 25, 2021	1,028		—		—		1,450		2,478
Restructuring charges	7,269		7,629		186		502		15,586
Cash payments	(7,048)		(1,112)		(112)		(1,719)		(9,991)
Adjustment to restructuring charges	—		—		—		(147)		(147)
Non-cash settlement	—		(6,517)		(74)		(86)		(6,677)
December 31, 2022	$	1,249	$	—	$	—	$	—	$	1,249

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2022

Equity [Abstract]

Schedule of Restricted Stock Unit Activity

RSU activity was as follows:


	Number of Shares	Weighted Average Grant Date Fair Value
Restricted stock units at December 25, 2021	2,166,934	$	28.63
Granted	1,356,948	34.83
Vested	(1,156,130)	22.60
Canceled	(140,671)	32.73
Restricted stock units at December 31, 2022	2,227,081	35.28

Schedule of Performance Restricted Stock Unit Activity

PRSU grant activity was as follows:

Fiscal Year Ended

December 31, 2022

December 25, 2021

December 26, 2020

Grant Date

August 1, 2022

August 2, 2021

August 27, 2020

Performance period

July 1, 2022 - June 30, 2025

July 1, 2021 - June 30, 2024

July 1, 2020 - June 30, 2023

Number of shares

204,903

197,128

258,000

TSR as-of date

August 1, 2022

August 2, 2021

August 27, 2020

Stock-based compensation

$8.6 million

$6.9 million

Income Taxes - Components of Income Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
United States	$ 30,047	$ 74,298	$ 72,950
Foreign	27,823	24,202	12,225
Income before income taxes	$ 57,870	$ 98,500	$ 85,175

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Schedule of Components of Income Before Income Taxes

The components of income before income taxes were as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
United States	$	30,047	$	74,298	$	72,950
Foreign	27,823		24,202		12,225
	$	57,870	$	98,500	$	85,175

Schedule of Components of Provision for Income Taxes

The components of the provision for income taxes are as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Current provision:
Federal	$	4,330	$	2,334	$	1,799
State	520		712		1,194
Foreign	8,625		7,661		4,278
	13,475		10,707		7,271
Deferred provision (benefit):
Federal	(5,886)		4,651		1,472
State	118		522		(267)
Foreign	(575)		(1,304)		(1,824)
	(6,343)		3,869		(619)
Total provision for income taxes	$	7,132	$	14,576	$	6,652

Schedule of Effective Income Tax Rate Reconciliation

The following is a reconciliation of the difference between income taxes computed by applying the federal statutory rate of 21% and the provision from income taxes (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
U.S. statutory federal tax rate	$	12,153	$	20,685	$	17,887
State taxes and credits, net of federal benefit	16		811		663
Stock-based compensation	(2,772)		(6,118)		(4,962)
Research and development credits	(8,264)		(7,153)		(6,576)
Foreign taxes at rates different than the U.S.	2,404		2,286		415
Other permanent differences	1,964		2,043		400
Global intangible low-taxed income	7		—		—
Foreign derived intangible income	(5,160)		(2,486)		(3,668)
Change in valuation allowance	2,597		2,231		1,862
Tax contingencies, net of reversals	3,124		2,812		2,712
Other	1,063		(535)		(2,081)
Total	$	7,132	$	14,576	$	6,652

Schedule of Deferred Tax Assets and Liabilities

Significant deferred tax assets and liabilities consisted of the following (in thousands):


	As of
	December 31, 2022		December 25, 2021
Tax credits	$	33,025	$	41,650
Inventory reserve	14,269		13,691
Other reserves and accruals	6,527		8,523
Non-statutory stock options	3,180		2,837
Lease liability	6,024		6,717
Research and development expenditures capitalization	36,821		19,553
Net operating loss carryforwards	18,173		18,395
Gross deferred tax assets	118,019		111,366
Valuation allowance	(43,295)		(40,698)
Total deferred tax assets	74,724		70,668
Right-of-use assets	(5,219)		(5,910)
Acquired intangibles and fixed assets	(4,342)		(6,163)
Unrealized investment gains	(103)		(105)
Tax on undistributed earnings	(146)		(118)
Total deferred tax liabilities	(9,810)		(12,296)
Net deferred tax assets	$	64,914	$	58,372

Summary of Tax Credit Carryforwards

Tax credits and carryforwards available to us at December 31, 2022 consisted of the following (in thousands):


	Amount		Latest Expiration Date
Federal research and development tax credit	$	26,424	2034-2042
Foreign tax credit carryforwards	995		2023-2027
California research credits	52,131		Indefinite
State net operating loss carryforwards	249,087		2025-Indefinite
Singapore net operating loss carryforwards	5,724		Indefinite

Schedule of Unrecognized Tax Benefits

The following table reflects changes in the unrecognized tax benefits (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Unrecognized tax benefit, beginning balance	$	35,745	$	32,497	$	28,800
Additions based on tax positions related to the current year	3,868		3,201		3,072
Additions based on tax positions from prior years	795		124		702
Reductions for tax positions of prior years	—		—		—
Reductions due to lapse of the applicable statute of limitations	(310)		(77)		(77)
Unrecognized tax benefit, ending balance	$	40,098	$	35,745	$	32,497

Interest and penalties recognized as a component of provision for income taxes	$	30	$	40	$	50
Interest and penalties accrued at period end	85		188		204

Goodwill and Intangible Assets

12 Months Ended

Dec. 31, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

Goodwill

Goodwill by reportable segment was as follows (in thousands):


	Probe Cards		Systems		Total
Goodwill, as of December 26, 2020	$	178,072	$	34,689	$	212,761

Addition - Baldwin Park acquisition	352		—		352
Addition - HPD acquisition	—		1,254		1,254
Foreign currency translation	—		(2,068)		(2,068)
Goodwill, as of December 25, 2021	178,424		33,875		212,299

Addition - Woburn acquisition	—		550		550
Foreign currency translation	—		(1,405)		(1,405)
Goodwill, as of December 31, 2022	$	178,424	$	33,020	$	211,444

Intangible Assets

Intangible assets were as follows (in thousands):


	December 31, 2022						December 25, 2021
Other Intangible Assets	Gross		Accumulated Amortization		Net		Gross		Accumulated Amortization		Net
Existing developed technologies	$	171,441	$	151,212	$	20,229	$	172,259	$	148,784	$	23,475
Trade name	7,972		7,759		213		8,054		7,603		451
Customer relationships	50,912		45,003		5,909		51,270		39,254		12,016
Backlog	—		—		—		1,896		1,896		—
In-process research and development	400		—		400		400		—		400
	$	230,725	$	203,974	$	26,751	$	233,879	$	197,537	$	36,342

Amortization expense was included in our Consolidated Statements of Income as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Cost of revenues	$	3,225	$	12,269	$	21,609
Selling, general and administrative	6,166		6,478		6,382
	$	9,391	$	18,747	$	27,991

The estimated future amortization of definite-lived intangible assets, excluding in-process research and development, is as follows (in thousands):


Fiscal Year	Amount
2023	$	7,166
2024	4,584
2025	4,243
2026	3,155
2027	2,816
Thereafter	4,387
Total	$	26,351

We did not record any impairment of intangible assets in fiscal 2022, 2021 and 2020.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Consolidation and Foreign Currency Translation

The consolidated financial statements include our accounts and those of our wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.

The functional currencies of certain of our foreign subsidiaries are the local currencies and, accordingly, all assets and liabilities of these foreign operations are translated to U.S. Dollars at current period-end exchange rates, and revenues and expenses are translated to U.S. Dollars using average exchange rates in effect during the period. The gains and losses from the foreign currency translation of these subsidiaries' financial statements are included as a separate component of stockholders' equity on our Consolidated Balance Sheets under Accumulated other comprehensive loss.

Certain other of our foreign subsidiaries use the U.S. Dollar as their functional currency. Accordingly, monetary assets and liabilities in non-functional currencies of these subsidiaries are remeasured using exchange rates in effect at the end of the period. Revenues and costs in local currency are remeasured using average exchange rates for the period, except for costs related to those balance sheet items that are remeasured using historical exchange rates. The resulting remeasurement gains and losses are included in the Consolidated Statements of Income as a component of Other income, net as incurred.

Use of Estimates

The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Estimates may change as new information is obtained. We believe that the estimates, assumptions and judgments involved in revenue recognition, fair value of marketable securities, fair value of derivative financial instruments used to hedge both foreign currency and interest rate exposures, allowance for credit losses, reserves for product warranty, valuation of obsolete and slow moving inventory, assets acquired and liabilities assumed in business combinations, legal contingencies, valuation of goodwill, the assessment of recoverability of long-lived assets, valuation and recognition of stock-based compensation, loss contingencies, provision for income taxes and valuation of deferred tax assets have the greatest potential impact on our consolidated financial statements. Actual results could differ from those estimates.

Business Acquisitions

Our consolidated financial statements include the operations of acquired businesses after the completion of their respective acquisitions. We account for acquired businesses using the acquisition method of accounting, which requires, among other

things, that assets acquired and liabilities assumed be recognized at their estimated fair values as of the acquisition date, and that the fair value of acquired intangibles be recorded on the balance sheet. Transaction costs are expensed as incurred. Any excess of the purchase price over the assigned fair values of the net assets acquired is recorded as goodwill.

Cash and Cash Equivalents and Marketable Securities

Cash and cash equivalents consist of deposits and financial instruments which are readily convertible into cash and have original maturities of 90 days or less at the time of acquisition. Marketable securities consist primarily of highly liquid investments with maturities of greater than 90 days when purchased. We classify our available-for-sale marketable securities as current assets because they represent investments of cash available for current operations. As a result, the Company recorded all its marketable securities in short-term investments regardless of the contractual maturity date of the securities. Furthermore, we report them at fair value with the related unrealized gains and losses included in Accumulated other comprehensive loss in our Consolidated Balance Sheets. Any unrealized losses which are considered to be other-than-temporary are recorded in Other income, net, in the Consolidated Statements of Income. Realized gains and losses on the sale of marketable securities are determined using the specific-identification method and recorded in Other income, net, in the Consolidated Statements of Income.

All of our available-for-sale investments are subject to a periodic impairment review. If an available-for-sale debt security’s fair value is less than its amortized cost basis, then we evaluate whether the decline is the result of a credit loss, in which case an impairment is recorded through an allowance for credit losses. Unrealized gains and losses not attributable to credit losses are included, net of tax, in Accumulated other comprehensive loss in our Consolidated Balance Sheets. We did not record an allowance for credit losses related to our available-for-sale investments during fiscal 2022.

Foreign Exchange Management

We transact business in various foreign currencies. We enter into forward foreign exchange contracts in an effort to mitigate the risks associated with currency fluctuations on certain foreign currency balance sheet exposures and certain operational costs denominated in local currency impacting our statement of income. For accounting purposes, certain of our foreign currency forward contracts are not designated as hedging instruments and, accordingly, we record the fair value of these contracts as of the end of our reporting period in our Consolidated Balance Sheets with changes in fair value recorded within Other income, net in our Consolidated Statements of Income for both realized and unrealized gains and losses. Certain of our foreign currency forward contracts are designated as cash flow hedges, and, accordingly, we record the fair value of these contracts as of the end of our reporting period in our Consolidated Balance Sheets with changes in fair value recorded as a component of Accumulated other comprehensive loss and reclassified into earnings in the same period in which the hedged transaction affects earnings, and in the same line item on the Consolidated Statements of Income as the impact of the hedge transaction. We do not use derivative financial instruments for trading or speculative purposes.

Accounts Receivable and Allowance for Credit Losses

The majority of our accounts receivable are derived from sales to large multinational semiconductor manufacturers throughout the world, are recorded at their invoiced amount, and do not bear interest.

In order to monitor potential credit losses, we perform ongoing credit evaluations of our customers' financial condition. An allowance for credit losses is maintained based upon our assessment of the expected collectability of all accounts receivable. The allowance for credit losses is reviewed and assessed for adequacy on a quarterly basis. We take into consideration (1) any circumstances of which we are aware of a customer's inability to meet its financial obligations and (2) our judgments as to prevailing economic conditions in the industry and their impact on our customers. If circumstances change, and the financial condition of our customers is adversely affected and they are unable to meet their financial obligations, we may need to take additional allowances, which would result in an increase in our operating expense.

Activity related to our allowance for credit losses was as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Balance at beginning of year	$	195	$	248	$	222
Charges (reversals) to costs and expenses	(27)		(53)		26
Balance at end of year	$	168	$	195	$	248

Inventories

We state our inventories at the lower of cost (principally standard cost which approximates actual cost on a first in, first out basis) or net realizable value. We regularly assess the value of our inventory and will periodically write down its value for estimated excess inventory and product obsolescence based upon an analysis of existing inventory quantities compared to estimated future consumption. Future consumption is estimated based upon assumptions about how past consumption, recent purchases, backlog and other factors may indicate future consumption. On a quarterly basis, we review existing inventory quantities in comparison to our past consumption, recent purchases, backlog and other factors to determine what inventory quantities, if any, may not be sellable. Based on this analysis, we record an adjustment to the cost basis of inventory when evidence exists that the net realizable value of inventory is lower than its cost, which occurs when we have excess and/or obsolete inventory. Once the value is adjusted, the original cost of our inventory, less the related inventory write-down, represents the new cost basis. Reversal of these write downs is recognized only when the related inventory has been scrapped or sold. Shipping and handling costs are classified as a component of Cost of revenues in the Consolidated Statements of Income.

We design, manufacture and sell a custom product into a market that has been subject to cyclicality and significant demand fluctuations. Many of our products are complex, custom to a specific chip design and have to be delivered on short lead-times. Probe cards are manufactured in low volumes, but, for certain materials, the purchases are often subject to minimum order quantities in excess of the actual underlying probe card demand. It is not uncommon for us to acquire production materials and commence production activities based on estimated production yields and forecasted demand prior to, or in excess of, actual demand for our probe cards. These factors result in normal recurring inventory valuation charges to Cost of revenues.

Inventory write downs totaled $24.6 million, $15.5 million and $13.1 million for fiscal 2022, 2021 and 2020, respectively.

Restricted Cash

Restricted cash is comprised primarily of funds held by our foreign subsidiaries for employee obligations, office leases, customer deposits, temporary customs import permits, and environmental remediation.

Property, Plant, and Equipment

Property, plant and equipment is stated at cost less accumulated depreciation and amortization. Depreciation is recorded on a straight-line method. Machinery and equipment, computer equipment and software, and furniture and fixtures are depreciated over 3 to 5 years. Leasehold improvements are amortized over 7 years. Building and building improvements are depreciated over 30 years. Construction-in-progress assets are not depreciated until the assets are placed in service. Upon sale or retirement of assets, the cost and related accumulated depreciation or amortization are removed from the Consolidated Balance Sheets and the resulting gain or loss, if any, is reflected in Operating income in our Consolidated Statements of Income.

Leases

The Company determines if an arrangement is a lease at its inception. Right-of-use (“ROU”) assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. We use our estimated incremental borrowing rate in determining the present value of lease payments considering the term of the lease, which is derived from information available at the lease commencement date. The lease term includes renewal options when it is reasonably certain that the option will be exercised and excludes termination options. To the extent that the Company’s agreements have variable lease payments, the Company includes variable lease payments that depend on an index or a rate and excludes those that depend on facts or circumstances occurring after the commencement date, other than the passage of time.

Lease expense for these leases is recognized on a straight-line basis over the lease term. We have elected not to recognize ROU assets and lease liabilities that arise from short-term leases for any class of underlying asset. Operating leases are included in Operating lease, right-of-use-assets, Operating lease liabilities, and Long-term operating lease liabilities in our Consolidated Balance Sheets.

Goodwill

Goodwill represents the excess of the purchase price over the fair value of identifiable assets acquired and liabilities assumed. Goodwill is not amortized, rather assessed, at least annually, for impairment at a reporting unit level. Impairment of goodwill exists when the carrying amount of a reporting unit exceeds its fair value. A goodwill impairment loss is recognized for the amount that the carrying amount of the reporting unit, including goodwill, exceeds its fair value, limited to the total amount of goodwill allocated to that reporting unit. If the fair value of a reporting unit exceeds the carrying amount, goodwill of the reporting unit is not considered impaired.

We evaluate impairment by first assessing qualitative factors to determine whether it is necessary to perform a quantitative impairment test. If we determine, as a result of the qualitative assessment, that it is more likely than not that the fair value of a

reporting unit is less than its carrying amount, then the quantitative impairment test is required. Otherwise, no further testing is required.

We perform our annual goodwill impairment test in the fourth quarter of each year by assessing qualitative factors, including, but not limited to, an assessment of our market capitalization, which was significantly higher than our book value. Based on these tests, we determined that the quantitative impairment test was not required and no impairment charges were recorded in fiscal 2022, 2021 or 2020.

The evaluation of goodwill for impairment requires the exercise of judgment. In the event of future changes in business conditions, we will be required to reassess and update our forecasts and estimates used in future impairment analysis. If the results of these analysis are lower than current estimates, a material impairment charge may result at that time.

See Note 10, Goodwill and Intangible Assets, for additional information.

Intangible Assets

Intangible assets consist of acquisition related intangible assets and intellectual property. The intangible assets are being amortized over periods of 1 to 10 years, which reflect the pattern in which economic benefits of the assets are expected to be realized. We perform a review of intangible assets when facts and circumstances indicate that the useful life is shorter than originally estimated or that the carrying amount of assets may not be recoverable. Such facts and circumstances include significant adverse changes in the business climate or legal factors; current period cash flow or operating losses combined with a history of losses or a forecast of continuing losses associated with the use of the intangible assets; and current expectation that the intangible assets will more likely than not be sold or disposed of before the end of their estimated useful lives. We assess the recoverability of identified intangible assets by comparing the projected undiscounted net cash flows associated with the related asset or group of assets over their remaining lives against their respective carrying amounts. Impairments, if any, are based on the excess of the carrying amount over the fair value of those assets.

See Note 10, Goodwill and Intangible Assets, for additional information.

Impairment of Long-Lived Assets

We test long-lived assets or asset groups, such as property, plant and equipment and intangible assets, for recoverability when events or changes in circumstances indicate that their carrying amounts may not be recoverable. Circumstances which could trigger a review include, but are not limited to: significant decreases in the market price of the asset; significant adverse changes in the business climate or legal factors; accumulation of costs significantly in excess of the amount originally expected for the acquisition or construction of the asset; current period cash flow or operating losses combined with a history of losses or a forecast of continuing losses associated with the use of the asset; and current expectation that the asset will more likely than not be sold or disposed of before the end of its estimated useful life.

Recoverability is assessed based on the carrying amounts of the asset or asset group and the sum of the undiscounted cash flows expected to result from the use and the eventual disposal of the asset. An impairment loss is recognized when the carrying amount is not recoverable and exceeds fair value.

Concentration of Credit Risk and Other Risks and Uncertainties

Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash equivalents, marketable securities and accounts receivable. Our cash equivalents and marketable securities are held in safekeeping by large, credit-worthy financial institutions. We invest our excess cash primarily in U.S. banks, government and agency bonds, money market funds and corporate obligations. We have established guidelines relative to credit ratings, diversification and maturities that seek to maintain safety and liquidity. Deposits in these banks may exceed the amounts of insurance provided on such deposits. To date, we have not experienced any losses on our deposits of cash and cash equivalents. We market and sell our products to a relatively narrow base of customers and generally do not require collateral.

The following customers represented 10% or more of our revenues:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Intel Corporation	19.0	%	20.4	%	31.5	%
Samsung Electronics Co., LTD.	*		11.4		*

* Less than 10% of revenues.

At December 31, 2022, one customer accounted for 13.8% of gross accounts receivable. At December 25, 2021, one customer accounted for 13.8% of gross accounts receivable. No other customers accounted for 10% or more of gross accounts receivable for these fiscal period ends.

We are exposed to non-performance risk by counterparties on our derivative instruments used in hedging activities. We seek to minimize risk by diversifying our hedging program across multiple financial institutions. These counterparties are large international financial institutions, and, to date, no such counterparty has failed to meet its financial obligations to us.

Revenue Recognition

Revenue is recognized upon transferring control of products and services, and the amounts recognized reflect the consideration we expect to be entitled to receive in exchange for these products and services. Revenue is recognized net of any taxes collected from customers, which are subsequently remitted to governmental authorities. An arrangement may include some or all of the following products and services: probe cards, systems, accessories, engineering services, installation services, service contracts and extended warranty contracts. We sell our products and services direct to customers and to partners in two distribution channels: global direct sales force and through a combination of manufacturers’ representatives and distributors.

A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. In contracts with multiple performance obligations, we identify each performance obligation and evaluate whether the performance obligation is distinct within the context of the contract at contract inception. Performance obligations that are not distinct at contract inception are combined and accounted for as one unit of account. Generally, the performance obligations in a contract are considered distinct within the context of the contract and are accounted for as separate units of account.

Our products may be customized to our customers’ specifications; however, control of our product is typically transferred to the customer at the point in time the product is either shipped or delivered, depending on the terms of the arrangement, as the criteria for over time recognition is not met. In limited circumstances, substantive acceptance by the customer exists which results in the deferral of revenue until acceptance is formally received from the customer. Judgment may be required in determining if the acceptance clause is substantive. In certain instances control of products is transferred to the customer over time based on performance and in those instances we utilize an appropriate input or output measure to determine to what extent control has transferred to the customer. Judgment may be required in determining an appropriate measure of performance.

Installation services are routinely provided to customers purchasing our systems. Installation services are a distinct performance obligation apart from the systems and are recognized in the period they are performed. Service contracts, which include repair and maintenance service contracts, and extended warranty contracts are also distinct performance obligations and are recognized over the contractual service period, which ranges from one to three years. For these service contracts recognized over time, we use the input measure of days elapsed to measure progress.

A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. In determining the transaction price, we evaluate whether the price is subject to refund or adjustment to determine the net consideration to which we expect to be entitled. We generally do not grant return privileges, except for defective products during the warranty period. Sales incentives and other programs that we may make available to our customers are considered to be a form of variable consideration, which is estimated in determining the contract’s transaction price to be allocated to the performance obligations.

For contracts with multiple performance obligations, we allocate the contract’s transaction price to each performance obligation based on its relative stand-alone selling price. The stand-alone selling prices are determined based on observable prices, which are the prices at which we separately sell these products. For items which do not have observable prices, we use our best estimate of the stand-alone selling prices.

Transaction price allocated to the remaining performance obligations: On December 31, 2022, we had $7.5 million of remaining performance obligations, which were comprised of deferred service contracts, extended warranty contracts, and contracts with over time revenue recognition that are not yet delivered. We expect to recognize approximately 85.7% of our remaining performance obligations as revenue in fiscal 2023, approximately 9.6% in fiscal 2024, and approximately 4.7% in fiscal 2025 and thereafter. The foregoing excludes the value of remaining performance obligations that have original durations of one year or less, and also excludes information about variable consideration allocated entirely to a wholly unsatisfied performance obligation.

Contract balances: The timing of revenue recognition may differ from the timing of invoicing to customers. Accounts receivable is recorded at the invoiced amount, net of an allowance for credit losses. A receivable is recognized in the period we deliver goods or provide services or when our right to consideration is unconditional. A contract asset is recorded when we have performed under the contract but our right to consideration is conditional on something other than the passage of time. Contract assets as of December 31, 2022 and December 25, 2021 were $1.9 million and $0.9 million, respectively, and are reported on the Consolidated Balance Sheets as a component of Prepaid expenses and other current assets.

Contract liabilities include payments received and payments due in advance of performance under a contract and are satisfied as the associated revenue is recognized. Contract liabilities are reported on the Consolidated Balance Sheets on a contract-by-contract basis at the end of each reporting period as a component of Deferred revenue and Other liabilities. Contract liabilities totaled $30.9 million and $24.2 million at December 31, 2022 and December 25, 2021, respectively. During fiscal 2022, we recognized $20.1 million of revenue that was included in contract liabilities as of December 25, 2021.

Costs to obtain a contract: We generally expense sales commissions when incurred as a component of Selling, general and administrative expense as the amortization period is typically less than one year.

Revenue by Category: Refer to Note 16, Segments and Geographic Information, for further details.

Warranty Obligations

We offer warranties on certain products and record a liability for the estimated future costs associated with warranty claims at the time revenue is recognized. The warranty liability is based upon historical experience and our estimate of the level of future costs. While we engage in product quality programs and processes, our warranty obligation is affected by product failure rates, material usage and service delivery costs incurred in correcting a product failure. We continuously monitor product returns for warranty and maintain a reserve for the related expenses based upon our historical experience and any specifically identified field failures. As we sell new products to our customers, we must exercise considerable judgment in estimating the expected failure rates. This estimating process is based on historical experience of similar products, as well as various other assumptions that we believe to be reasonable under the circumstances.

We provide for the estimated cost of product warranties at the time revenue is recognized. Warranty costs are reflected in the Consolidated Statement of Income as a Cost of revenues.

A reconciliation of the changes in our warranty liability is as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Balance at beginning of year	$	2,805	$	3,918	$	1,942
Accruals	7,746		5,759		5,727
Settlements	(6,352)		(6,872)		(3,751)
Balance at end of year	$	4,199	$	2,805	$	3,918

Research and Development

Research and development expenses include expenses related to product development, engineering and material costs. All research and development costs are expensed as incurred.

Income Taxes

We utilize the asset and liability method of accounting for income taxes, under which deferred taxes are determined based on the temporary differences between the financial statement and tax basis of assets and liabilities using tax rates expected to be in effect during the years in which the basis differences reverse and for operating losses and tax credit carryforwards. We estimate our provision for income taxes and amounts ultimately payable or recoverable in numerous tax jurisdictions around the world. Estimates involve interpretations of regulations and are inherently complex. Resolution of income tax treatments in individual jurisdictions may not be known for many years after completion of any fiscal year. We are required to evaluate the realizability of our deferred tax assets on an ongoing basis to determine whether there is a need for a valuation allowance with respect to such deferred tax assets. A valuation allowance is recorded when it is more likely than not that some or all of the deferred tax assets will not be realized. In evaluating the ability to recover deferred tax assets, we consider all available positive and negative evidence giving greater weight to our recent cumulative income, our historical ability to utilize net operating losses in recent years, and our forecast of future taxable income, including the reversal of temporary differences and the implementation of feasible and prudent tax planning strategies.

We recognize and measure uncertain tax positions taken or expected to be taken in a tax return if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized are then measured based on the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement. We report a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. We adjust these reserves in light of changing facts and circumstances, such as the closing of a tax audit or the refinement of an estimate. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will impact the provision for income taxes in the period in which such determination is made. The provision for income taxes includes the impact of reserve provisions and changes to reserves, as well as the related net interest. We recognize interest and penalties related to unrecognized tax benefits within the income tax provision. Accrued interest and penalties are included within the related tax liability in the Consolidated Balance Sheets.

We file annual income tax returns in multiple taxing jurisdictions around the world. A number of years may elapse before an uncertain tax position is audited and finally resolved. While it is often difficult to predict the final outcome or the timing of resolution of any particular uncertain tax position, we believe that our related liability reflects the most likely outcome. We adjust the liability, as well as the related interest, in light of changing facts and circumstances. Settlement of any particular position could require the use of cash.

Stock-Based Compensation

We recognize compensation expense for all stock-based awards based on the grant-date estimated fair values. The value of the portion of the award that is ultimately expected to vest is recognized as expense ratably over the requisite service periods in our Consolidated Statements of Income. The fair value of restricted stock units (“RSUs”) is measured based on the closing market price of our common stock on the date of grant. The fair value of Performance RSUs (“PRSU”) is based on certain market performance criteria and is measured using a Monte Carlo simulation pricing model.

See Note 12, Stockholders' Equity, and Note 13, Stock-Based Compensation, for additional information.

Net Income Per Share

Basic net income per share is computed by dividing net income by the weighted-average number of common shares outstanding for the period. Diluted net income per share is computed giving effect to all potentially dilutive common stock and common stock equivalents, including stock options, RSUs and common stock subject to repurchase.

The following table reconciles the shares used in calculating basic net income per share and diluted net income per share (in thousands):


	Fiscal Year Ended
	December 31, 2022	December 25, 2021	December 26, 2020



Weighted-average shares used in computing basic net income per share	77,578	77,787	76,681
Add potentially dilutive securities	623	1,346	2,320
Weighted-average shares used in computing basic and diluted net income per share	78,201	79,133	79,001

Accumulated other comprehensive loss

Accumulated other comprehensive loss (“OCI/L”) includes the following items, the impact of which has been excluded from earnings and reflected as components of stockholders' equity as shown below (in thousands):


	December 31, 2022		December 25, 2021
Unrealized losses on available-for-sale marketable securities and other investments	$	(2,749)	$	(724)
Translation adjustments	(5,675)		(811)
Unrealized gains on derivative instruments	2,846		86
Accumulated other comprehensive loss	$	(5,578)	$	(1,449)

Segments and Geographic Information - Long-Lived Assets by Geographical Location (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Long-Lived Assets [Line Items]
Long-lived assets	$ 459,405	$ 430,406	$ 406,767
United States
Long-Lived Assets [Line Items]
Long-lived assets	406,529	372,338	347,654
Europe
Long-Lived Assets [Line Items]
Long-lived assets	42,640	47,700	51,791
Asia Pacific [Member]
Long-Lived Assets [Line Items]
Long-lived assets	$ 10,236	$ 10,368	$ 7,322

Fair Value

3 Months Ended

Mar. 26, 2022

Fair Value Disclosures [Abstract]

Fair Value

Whenever possible, the fair values of our financial assets and liabilities are determined using quoted market prices of identical securities or quoted market prices of similar securities from active markets. The three levels of inputs that may be used to measure fair value are as follows:

•Level 1 valuations are obtained from real-time quotes for transactions in active exchange markets involving identical securities;

•Level 2 valuations utilize significant observable inputs, such as quoted prices for similar assets or liabilities, quoted prices near the reporting date in markets that are less active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and

•Level 3 valuations utilize unobservable inputs to the valuation methodology and include our own data about assumptions market participants would use in pricing the asset or liability based on the best information available under the circumstances.

We did not have any transfers of assets or liabilities measured at fair value on a recurring basis to or from Level 1, Level 2 or Level 3 during fiscal 2022, 2021 or 2020.

The carrying values of Cash, Accounts receivable, net, Restricted cash, Prepaid expenses and other current assets, Accounts payable, and Accrued liabilities approximate fair value due to their short maturities.

No changes were made to our valuation techniques during fiscal 2022.

Cash Equivalents

The fair value of our cash equivalents is determined based on quoted market prices for similar or identical securities.

Marketable Securities

We classify our marketable securities as available-for-sale and value them utilizing a market approach. Our investments are priced by pricing vendors who provide observable inputs for their pricing without applying significant judgment. Broker pricing is used mainly when a quoted price is not available, the investment is not priced by our pricing vendors or when a broker price is more reflective of fair value. Our broker-priced investments are categorized as Level 2 investments because fair value is based on similar assets without applying significant judgments. In addition, all of our investments have a sufficient level of trading volume to demonstrate that the fair value is appropriate.

Assets and liabilities Measured at Fair Value on a Recurring Basis

Assets and liabilities measured at fair value on a recurring basis were as follows (in thousands):


December 31, 2022	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	21,279	$	—	$	—	$	21,279

Commercial paper	—		4,969		—		4,969
U.S. agency securities	—		996		—		996
	21,279		5,965		—		27,244
Marketable securities:
U.S. treasuries	25,019		—		—		25,019
Certificates of deposit	—		706		—		706
U.S. agency securities	—		11,045		—		11,045
Corporate bonds	—		67,396		—		67,396
Commercial paper	—		24,840		—		24,840
	25,019		103,987		—		129,006
Foreign exchange derivative contracts	—		664		—		664
Promissory note receivable	—		—		943		943
Interest rate swap derivative contracts	—		2,374		—		2,374
Total assets	$	46,298	$	112,990	$	943	$	160,231
Liabilities:
Foreign exchange derivative contracts	$	—	$	(193)	$	—	$	(193)


Total liabilities	$	—	$	(193)	$	—	$	(193)


December 25, 2021	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	9,526	$	—	$	—	$	9,526
U.S. treasuries	2,500		—		—		2,500
Commercial paper	—		1,000		—		1,000
U.S. agency securities	—		5,556		—		5,556
	12,026		6,556		—		18,582
Marketable securities:
U.S. treasuries	38,985		—		—		38,985
Certificates of deposit	—		1,199		—		1,199

Corporate bonds	—		52,709		—		52,709
Commercial paper	—		32,162		—		32,162
	38,985		86,070		—		125,055

Interest rate swap derivative contracts	—		629		—		629
Total assets	$	51,011	$	93,255	$	—	$	144,266
Liabilities:
Foreign exchange derivative contracts	$	—	$	(489)	$	—	$	(489)
Interest rate swap derivative contracts	$	—	$	(55)	$	—	$	(55)

Total liabilities	$	—	$	(544)	$	—	$	(544)

Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis

We measure and report our non-financial assets such as Property, plant and equipment, Goodwill and Intangible assets at fair value on a non-recurring basis if we determine these assets to be impaired or in the period when we make a business acquisition. Other than as discussed in Note 4, Acquisitions and Note 7, Restructuring Charges, there were no assets or liabilities measured at fair value on a non-recurring basis during fiscal 2022, 2021 or 2020.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plans (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Retirement Benefits [Abstract]
Cost recognized under defined contribution plans	$ 2.7	$ 2.7	$ 2.2

Debt - Future Principle and Interest Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Debt Instrument [Line Items]
Principal, 2022	$ 1,050
Principal, 2023	1,080
Principal, 2024	1,111
Principal, 2025	1,142
Principal, 2026	1,175
Principal, 2027 and thereafter	9,941
Principal, total	15,499	$ 24,435
Interest, 2022	894
Interest, 2023	835
Interest, 2024	763
Interest, 2025	699
Interest, 2026	630
Interest, 2027 and thereafter	2,324
Interest, total	6,145
Total payments, 2022	1,944
Total payments, 2023	1,915
Total payments, 2024	1,874
Total payments, 2025	1,841
Total payments, 2026	1,805
Total payments, 2027 and thereafter	12,265
Long-term debt, maturities, total payments due	21,644
Building Term Loan
Debt Instrument [Line Items]
Principal, total	$ 15,500
Interest rate at period end	5.87%

Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2022

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Foreign Currency Forward Contracts Outstanding

The following table provides information about our foreign currency forward contracts outstanding as of December 31, 2022 (in thousands):


Currency	Contract Position	Contract Amount (Local Currency)	Contract Amount (U.S. Dollars)
Euro	Buy	21,576	$	22,615
Euro	Sell	4,927	5,107
Japanese Yen	Sell	2,989,654	22,906
Korean Won	Buy	2,067,724	1,639
Taiwan Dollar	Sell	42,826	1,397

The location and amount of gains (losses) related to foreign currency derivative instruments designated as cash flow hedges on our Consolidated Statements of Income was as follows (in thousands):


	Amount of Gain or (Loss) Recognized in Accumulated OCI/L on Derivative		Location of Gain or (Loss) Reclassified from Accumulated OCI/L into Income	Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income
Fiscal 2022	$	(1,688)	Cost of revenues	$	(1,816)
			Research and development	(376)
			Selling, general and administrative	(456)
				$	(2,648)

Fiscal 2021	$	(1,096)	Cost of revenues	$	184
			Research and development	3
			Selling, general and administrative	64
				$	251

Fiscal 2020	$	1,142	Cost of revenues	$	89
			Research and development	77
			Selling, general and administrative	25
				$	191

Schedule of Non-designated Derivative Gains (Losses)

The location and amount of gains (losses) related to non-designated derivative instruments in the Consolidated Statements of Income were as follows (in thousands):


	Location of Gain (Loss) Recognized on Derivatives	Fiscal Year Ended
Derivatives Not Designated as Hedging Instruments		December 31, 2022		December 25, 2021		December 26, 2020
Foreign exchange forward contracts	Other income, net	$	2,439	$	1,585	$	(1,437)

Schedule of the Impact of Cash Flow Hedges on Consolidated Financial Statements

The impact of the interest rate swaps on the Consolidated Statements of Income was as follows (in thousands):


	Amount of Gain or (Loss) Recognized in OCI/L on Derivative (Effective Portion)		Location of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)	Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)
Fiscal 2022	$	1,906	Other income, net	$	106
Fiscal 2021	451		Other income, net	(154)
Fiscal 2020	(119)		Other income, net	(64)

Stock-Based Compensation - Stock-based compensation details (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Share-Based Payment Arrangement [Abstract]
Weighted average grant date per share fair value of RSUs granted (in USD per share)	$ 34.83	$ 36.12	$ 25.96
Total intrinsic value of stock options exercised	$ 0	$ 3,179	$ 4,688
Fair value of RSUs vested	$ 42,324	$ 54,948	$ 42,597

Stock-Based Compensation - Valuation Assumptions (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Performance restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	53.00%	52.50%	52.00%
Risk-free interest rate	2.80%	0.30%	0.20%
Expected life (in years)	2 years 10 months 24 days	2 years 10 months 24 days	2 years 9 months 18 days
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Minimum \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	42.60%	33.60%	30.40%
Risk-free interest rate	0.10%	0.10%	0.10%
Expected life (in years)	6 months	6 months	6 months
Maximum \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	60.80%	74.40%	74.40%
Risk-free interest rate	3.00%	1.50%	1.50%
Expected life (in years)	1 year	1 year	1 year

Stock-Based Compensation - Unrecognized Stock-Based Compensation (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Expense	$ 58,366
Weighted Average Recognition Period (Years)	2 years 1 month 6 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Expense	$ 45,726
Weighted Average Recognition Period (Years)	2 years 1 month 6 days
Performance restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Expense	$ 12,216
Weighted Average Recognition Period (Years)	2 years
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Expense	$ 424
Weighted Average Recognition Period (Years)	1 month 6 days

Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

Goodwill by reportable segment was as follows (in thousands):


	Probe Cards		Systems		Total
Goodwill, as of December 26, 2020	$	178,072	$	34,689	$	212,761

Addition - Baldwin Park acquisition	352		—		352
Addition - HPD acquisition	—		1,254		1,254
Foreign currency translation	—		(2,068)		(2,068)
Goodwill, as of December 25, 2021	178,424		33,875		212,299

Addition - Woburn acquisition	—		550		550
Foreign currency translation	—		(1,405)		(1,405)
Goodwill, as of December 31, 2022	$	178,424	$	33,020	$	211,444

Schedule of Finite-lived Intangible Assets

Intangible assets were as follows (in thousands):


	December 31, 2022						December 25, 2021
Other Intangible Assets	Gross		Accumulated Amortization		Net		Gross		Accumulated Amortization		Net
Existing developed technologies	$	171,441	$	151,212	$	20,229	$	172,259	$	148,784	$	23,475
Trade name	7,972		7,759		213		8,054		7,603		451
Customer relationships	50,912		45,003		5,909		51,270		39,254		12,016
Backlog	—		—		—		1,896		1,896		—
In-process research and development	400		—		400		400		—		400
	$	230,725	$	203,974	$	26,751	$	233,879	$	197,537	$	36,342

Schedule of Amortization Expense

Amortization expense was included in our Consolidated Statements of Income as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Cost of revenues	$	3,225	$	12,269	$	21,609
Selling, general and administrative	6,166		6,478		6,382
	$	9,391	$	18,747	$	27,991

Schedule of Remaining Estimated Amortization Expense

The estimated future amortization of definite-lived intangible assets, excluding in-process research and development, is as follows (in thousands):


Fiscal Year	Amount
2023	$	7,166
2024	4,584
2025	4,243
2026	3,155
2027	2,816
Thereafter	4,387
Total	$	26,351

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=121556970&loc=SL108378252-109267

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 55
-Paragraph 24
-URI https://asc.fasb.org/extlink&oid=122137925&loc=d3e14258-109268

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

+ Details

Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 212,299	$ 212,761
Foreign currency translation	(1,405)	(2,068)
Goodwill, ending balance	211,444	212,299
Baldwin Park
Goodwill [Roll Forward]
Goodwill, acquired during period		352
High Precision Devices, Inc.
Goodwill [Roll Forward]
Goodwill, acquired during period		1,254
Woburn
Goodwill [Roll Forward]
Goodwill, acquired during period	550
Probe Cards
Goodwill [Roll Forward]
Goodwill, beginning balance	178,424	178,072
Foreign currency translation	0	0
Goodwill, ending balance	178,424	178,424
Probe Cards \| Baldwin Park
Goodwill [Roll Forward]
Goodwill, acquired during period		352
Probe Cards \| High Precision Devices, Inc.
Goodwill [Roll Forward]
Goodwill, acquired during period		0
Probe Cards \| Woburn
Goodwill [Roll Forward]
Goodwill, acquired during period	0
Systems
Goodwill [Roll Forward]
Goodwill, beginning balance	33,875	34,689
Foreign currency translation	(1,405)	(2,068)
Goodwill, ending balance	33,020	33,875
Systems \| Baldwin Park
Goodwill [Roll Forward]
Goodwill, acquired during period		0
Systems \| High Precision Devices, Inc.
Goodwill [Roll Forward]
Goodwill, acquired during period		$ 1,254
Systems \| Woburn
Goodwill [Roll Forward]
Goodwill, acquired during period	$ 550

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Finite-Lived Intangible Assets [Line Items]
Gross	$ 230,725	$ 233,879
Accumulated Amortization	203,974	197,537
Net	26,751	36,342
Existing developed technologies
Finite-Lived Intangible Assets [Line Items]
Gross	171,441	172,259
Accumulated Amortization	151,212	148,784
Net	20,229	23,475
Trade name
Finite-Lived Intangible Assets [Line Items]
Gross	7,972	8,054
Accumulated Amortization	7,759	7,603
Net	213	451
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross	50,912	51,270
Accumulated Amortization	45,003	39,254
Net	5,909	12,016
Backlog
Finite-Lived Intangible Assets [Line Items]
Gross	0	1,896
Accumulated Amortization	0	1,896
Net	0	0
In-process research and development
Finite-Lived Intangible Assets [Line Items]
Gross	400	400
Accumulated Amortization	0	0
Net	$ 400	$ 400

Acquisition (Tables)

12 Months Ended

Dec. 31, 2022

Business Combinations [Abstract]

Schedule of Assets Acquired and Liabilities Assumed

The fair value of assets acquired, including goodwill and intangibles, and liabilities assumed for the purchase are as follows (in thousands):


	Amount

Accounts receivable	178
Inventories	7,041
Property, plant and equipment	479

Prepaid expenses and other assets	117
Other asset	28
Tangible assets acquired	7,843
Deferred revenue	(5,513)
Accounts payable and accrued liabilities	(30)



Total net tangible assets acquired and liabilities assumed	2,300
Intangible assets	500
Goodwill	550
Net assets acquired	$	3,350

The purchase price allocated to the underlying assets acquired, including goodwill and intangibles, and liabilities assumed based on the final amounts are as follows (in thousands):


	Amount
Cash and cash equivalents	$	1,680
Accounts receivable	1,017
Inventory	3,047
Property, plant and equipment	669
Operating lease, right-of-use-assets	2,554
Prepaid expenses and other assets	916
Tangible assets acquired	9,883
Deferred revenue	(2,529)
Accounts payable and accrued liabilities	(1,268)
Operating lease liabilities	(2,554)
Deferred tax liability	(2,400)
Total net tangible assets acquired and liabilities assumed	1,132
Intangible assets	11,520
Goodwill	5,908
Net assets acquired	$	18,560

The purchase price allocated to the underlying assets acquired, including goodwill and intangibles, and liabilities assumed based on the final amounts are as follows (in thousands):


	Amount
Accounts receivable	$	4,365
Inventory	2,727
Property, plant and equipment	9,053
Operating lease, right-of-use-assets	519
Prepaid expenses and other assets	56
Tangible assets acquired	16,720
Accounts payable and accrued liabilities	(743)
Operating lease liabilities	(519)
Total net tangible assets acquired and liabilities assumed	15,458
Intangible assets	13,600
Goodwill	5,942
Net assets acquired	$	35,000

Summary of Finite-Lived Intangible Assets Acquired

The intangible assets as of the acquisition date included (in thousands):


	Amount		Weighted Average Useful Life (in years)
Developed technologies	$	7,500	10.0
Customer relationships	3,600		5.0
Order backlog	200		0.5
Trade names	220		5.0
Total intangible assets	$	11,520	8.2

The intangible assets as of the acquisition date included (in thousands):


	Amount		Weighted Average Useful Life (in years)
Developed technologies	$	8,800	10.0
Customer relationships	4,400		3.0
In-process research and development	400		N/A
Total intangible assets	$	13,600	7.7

Stockholders' Equity - Equity Incentive Plans (Details) - 2012 Plan	12 Months Ended
	Dec. 31, 2022 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)	27,400,000
Shares available for grant (in shares)	6,500,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years

Balance Sheet Components - Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Accrued Liabilities, Current [Abstract]
Accrued compensation and benefits	$ 15,864	$ 29,706
Accrued income and other taxes	12,817	8,086
Accrued employee stock purchase plan contributions withheld	4,585	4,693
Accrued warranty	4,199	2,805
Accrued restructuring charges	1,249	2,478	$ 0
Other accrued expenses	3,401	3,068
Total	$ 42,115	$ 50,836

Acquisition

12 Months Ended

Dec. 31, 2022

Business Combinations [Abstract]

Acquisition

Acquisitions

Woburn Acquisition

On June 9, 2022 we acquired the assets of the dilution refrigerator product line of American ULT Cryogenics, formerly d/b/a JanisULT (“Woburn”), for total consideration of $3.4 million. This acquisition adds cryogen-free dilution refrigerators capable of cooling to sub-10 millikelvin to our product portfolio, which is required for operation of superconducting quantum computers.

The acquisition price was allocated to the tangible and identified intangible assets acquired and liabilities assumed as of the closing date of the acquisition based upon their respective fair values. The fair values assigned to assets acquired and liabilities assumed were based on management’s assumptions as of the reporting date. Goodwill represents the excess of purchase price over the fair value assigned to the assets acquired and liabilities assumed and is allocated to the HPD reporting unit within the Systems reportable segment. The identified intangible asset, developed technology, has a useful life of three years.

The fair value of assets acquired, including goodwill and intangibles, and liabilities assumed for the purchase are as follows (in thousands):


	Amount

Accounts receivable	178
Inventories	7,041
Property, plant and equipment	479

Prepaid expenses and other assets	117
Other asset	28
Tangible assets acquired	7,843
Deferred revenue	(5,513)
Accounts payable and accrued liabilities	(30)



Total net tangible assets acquired and liabilities assumed	2,300
Intangible assets	500
Goodwill	550
Net assets acquired	$	3,350

High Precision Devises, Inc. (“HPD”) Acquisition

On October 19, 2020, we acquired 100% of the shares of HPD for total consideration of $16.9 million, net of cash acquired of $1.7 million, which included an adjustment for changes in working capital. This acquisition brought highly specialized skills and know-how to address the unique test challenges within the emerging quantum computing, superconducting computing, and ultra-sensitive sensor markets which operate at temperatures as low as 30 millikelvin.

The acquisition was accounted for using the acquisition method of accounting, with FormFactor treated as the acquirer. The acquired assets and liabilities of HPD were recorded at their respective fair values including an amount for goodwill representing the difference between the acquisition consideration and the fair value of the identifiable net assets.

Our Consolidated Statements of Income include the financial results of HPD subsequent to the acquisition date of October 19, 2020. Revenue in fiscal 2020 related to HPD subsequent to the acquisition date that was included in our Consolidated Statements of Income was not material.

identifiable assets and liabilities. The purchase price allocated to the underlying assets acquired, including goodwill and intangibles, and liabilities assumed based on the final amounts are as follows (in thousands):


	Amount
Cash and cash equivalents	$	1,680
Accounts receivable	1,017
Inventory	3,047
Property, plant and equipment	669
Operating lease, right-of-use-assets	2,554
Prepaid expenses and other assets	916
Tangible assets acquired	9,883
Deferred revenue	(2,529)
Accounts payable and accrued liabilities	(1,268)
Operating lease liabilities	(2,554)
Deferred tax liability	(2,400)
Total net tangible assets acquired and liabilities assumed	1,132
Intangible assets	11,520
Goodwill	5,908
Net assets acquired	$	18,560

The intangible assets as of the acquisition date included (in thousands):


	Amount		Weighted Average Useful Life (in years)
Developed technologies	$	7,500	10.0
Customer relationships	3,600		5.0
Order backlog	200		0.5
Trade names	220		5.0
Total intangible assets	$	11,520	8.2

The fair value of the intangible assets acquired in connection with the acquisition were determined using either the income, market or replacement cost methodologies. The intangible assets are being amortized over periods which reflect the pattern in which economic benefits of the assets are expected to be realized.

Identifiable Intangible Assets

Valuation of intangible assets involves multiple assumptions. The key assumptions are described below.

Developed technologies acquired primarily consist of existing technology related to cryogenic probe stations, Adiabatic Demagnetization Refrigerator (“ADR”), and continuous ADR cryostats and similar tools, and technology related to other cryogenic applications. We valued the developed technologies using the multi-period excess earnings method under the income approach. Using this approach, the estimated fair values were calculated using expected future cash flows from specific products discounted to their net present values at an appropriate risk-adjusted rate of return.

Customer relationships represent the fair value of future projected revenues that will be derived from the sale of products to HPD's existing customers. We valued customer relationships using the incremental cash flow method. This method estimates value based on the incremental cash flow afforded by having the customer relationships in place on the acquisition date versus having no relationships in place and needing to replicate or replace those relationships. The incremental cash flows are then discounted to a present value to arrive at an estimate of fair value for this asset class.

Order backlog represents business under existing contractual obligations. Expected cash flow from order backlog was valued on a discounted direct cash flow basis, net of returns on contributory assets such as working capital, property and equipment, trade name and assembled workforce.

The identified trade names intangibles relate to the estimated fair value of future cash flows related to the HPD brand. We valued trade names by applying the relief-from-royalty method under the income approach. This method is based on the application of a royalty rate to forecasted revenue under the trade name.

Goodwill

The excess of purchase price over the fair value assigned to the assets acquired and liabilities assumed represents the amount of goodwill resulting from the acquisition. We believe the factors that contributed to goodwill include synergies that are specific to our consolidated business, such as cost savings and operational efficiencies, and the acquisition of a talented workforce that expands our expertise in business development and commercializing semiconductor test products, none of which qualify for recognition as a separate intangible asset. We do not expect any portion of this goodwill to be deductible for tax purposes. The goodwill attributable to the acquisition was recorded as a non-current asset and is not amortized, but is subject to an annual review for impairment.

The goodwill arising from the acquisition was allocated to the HPD reporting unit within the Systems reportable segment.

We have not presented unaudited combined pro forma financial information as the HPD acquisition was not significant to our consolidated results of operations and financial position.

Baldwin Park Acquisition

On July 30, 2020, we acquired the probe card assets of Advantest Corporation for total cash consideration of $35.0 million. This acquisition brought important enabling technologies and capabilities for designing and manufacturing advanced probe cards, and adds a complementary 3D-NAND Flash probe card product that is qualified and in production at one of the world's leading NAND Flash manufacturers.

The acquisition was accounted for using the acquisition method of accounting, with FormFactor treated as the acquirer. The acquired assets and liabilities of Baldwin Park were recorded at their respective fair values including an amount for goodwill representing the difference between the acquisition consideration and the fair value of the identifiable net assets.

Our Consolidated Statements of Income include the financial results of Baldwin Park subsequent to the acquisition date of July 30, 2020. Revenue in fiscal 2020 related to Baldwin Park subsequent to the acquisition date that was included in our Consolidated Statements of Income was not material.

The acquisition price was allocated to the tangible and identified intangible assets acquired and liabilities assumed as of the closing date of the acquisition based upon their respective fair values. The fair values assigned to assets acquired and liabilities assumed were based on management’s assumptions as of the acquisition date. We subsequently made certain immaterial adjustments within the measurement period to the acquisition price allocation as a result of finalization of our valuation of identifiable assets and liabilities. The purchase price allocated to the underlying assets acquired, including goodwill and intangibles, and liabilities assumed based on the final amounts are as follows (in thousands):


	Amount
Accounts receivable	$	4,365
Inventory	2,727
Property, plant and equipment	9,053
Operating lease, right-of-use-assets	519
Prepaid expenses and other assets	56
Tangible assets acquired	16,720
Accounts payable and accrued liabilities	(743)
Operating lease liabilities	(519)
Total net tangible assets acquired and liabilities assumed	15,458
Intangible assets	13,600
Goodwill	5,942
Net assets acquired	$	35,000

The intangible assets as of the acquisition date included (in thousands):


	Amount		Weighted Average Useful Life (in years)
Developed technologies	$	8,800	10.0
Customer relationships	4,400		3.0
In-process research and development	400		N/A
Total intangible assets	$	13,600	7.7

Identifiable Intangible Assets

Valuation of intangible assets involves multiple assumptions. The key assumptions are described below.

Developed technologies acquired consists of existing technology related to 3D-NAND Flash probe cards and the value of cost savings expected to be derived from Low Temperature Co-fired Ceramic (“LTCC”) technology. We valued the developed technology related to 3D-NAND Flash using the multi-period excess earnings method under the income approach. Using this approach, the estimated fair values were calculated using expected future cash flows from specific products discounted to their net present values at an appropriate risk-adjusted rate of return. We valued the LTCC developed technology asset using the incremental cash flow method. This method estimates value based on the incremental cash flow afforded by having the LTCC capability in place on the acquisition date versus having no capability in place and needing to replicate or replace that capability. The incremental cash flows are then discounted to a present value to arrive at an estimate of fair value for this asset class.

In-process research and development (“IPR&D”) acquired primarily consists of research and development projects that were in process at the time of acquisition related to technologies used in DRAM probe cards. Once these projects are complete they will be placed in developed technologies and amortized over their useful lives. We valued the IPR&D using the multi-period excess earnings method under the income approach. Using this approach, the estimated fair values were calculated using expected future cash flows from specific products discounted to their net present values at an appropriate risk-adjusted rate of return.

Customer relationships represent the fair value of future projected revenues that will be derived from the sale of products to Baldwin Park's existing customers. We valued customer relationships using the incremental cash flow method. This method estimates value based on the incremental cash flow afforded by having the customer relationships in place on the acquisition date versus having no relationships in place and needing to replicate or replace those relationships. The incremental cash flows are then discounted to a present value to arrive at an estimate of fair value for this asset class.

Goodwill

The excess of purchase price over the fair value assigned to the assets acquired and liabilities assumed represents the amount of goodwill resulting from the acquisition. We believe the factors that contributed to goodwill include synergies that are specific to our consolidated business, such as cost savings and operational efficiencies, and the acquisition of a talented workforce that expands our expertise in business development, none of which qualify for recognition as a separate intangible asset. We expect this goodwill to be deductible for tax purposes. The goodwill attributable to the acquisition was recorded as a non-current asset and is not amortized, but is subject to an annual review for impairment.

The goodwill arising from the acquisition was allocated to the Probe Cards reporting unit within the Probe Cards reportable segment.

We have not presented unaudited combined pro forma financial information as the Baldwin Park acquisition was not significant to our consolidated results of operations and financial position.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balances (in shares) at Dec. 28, 2019		75,764,990
Beginning balances at Dec. 28, 2019	$ 640,997	$ 76	$ 885,821	$ (659)	$ (244,241)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under the Employee Stock Purchase Plan (in shares)		485,566
Issuance of common stock under the Employee Stock Purchase Plan	7,875	$ 0	7,875
Issuance of common stock pursuant to exercise of options for cash (in shares)		255,769
Issuance of common stock pursuant to exercise of options for cash	2,135	$ 1	2,134
Issuance of common stock pursuant to vesting of restricted stock units (in shares)		931,672
Issuance of common stock pursuant to vesting of restricted stock units, net of stock withheld for tax	(15,450)	$ 1	(15,451)
Stock-based compensation	23,459		23,459
Other comprehensive income (loss)	6,545			6,545
Net income	78,523				78,523
Ending balances (in shares) at Dec. 26, 2020		77,437,997
Ending balances at Dec. 26, 2020	744,084	$ 78	903,838	5,886	(165,718)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under the Employee Stock Purchase Plan (in shares)		378,584
Issuance of common stock under the Employee Stock Purchase Plan	9,809	$ 0	9,809
Issuance of common stock pursuant to exercise of options for cash (in shares)		100,000
Issuance of common stock pursuant to exercise of options for cash	844	$ 0	844
Issuance of common stock pursuant to vesting of restricted stock units (in shares)		946,325
Issuance of common stock pursuant to vesting of restricted stock units, net of stock withheld for tax	(20,603)	$ 1	(20,604)
Stock repurchased during the period (in shares)		622,400
Purchase and retirement of common stock	(24,038)	$ (1)	(24,037)
Stock-based compensation	29,095		29,095
Other comprehensive income (loss)	(7,335)			(7,335)
Net income	$ 83,924				83,924
Ending balances (in shares) at Dec. 25, 2021	78,240,506	78,240,506
Ending balances at Dec. 25, 2021	$ 815,780	$ 78	898,945	(1,449)	(81,794)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under the Employee Stock Purchase Plan (in shares)		316,861
Issuance of common stock under the Employee Stock Purchase Plan	10,457	$ 0	10,457
Issuance of common stock pursuant to exercise of options for cash (in shares)		6,000
Issuance of common stock pursuant to exercise of options for cash	42	$ 0	42
Issuance of common stock pursuant to vesting of restricted stock units (in shares)		728,524
Issuance of common stock pursuant to vesting of restricted stock units, net of stock withheld for tax	(15,705)	$ 1	(15,706)
Stock repurchased during the period (in shares)		2,377,301
Purchase and retirement of common stock	(82,328)	$ (2)	(82,326)
Stock-based compensation	33,430		33,430
Other comprehensive income (loss)	(4,129)			(4,129)
Net income	$ 50,738				50,738
Ending balances (in shares) at Dec. 31, 2022	76,914,590	76,914,590
Ending balances at Dec. 31, 2022	$ 808,285	$ 77	$ 844,842	$ (5,578)	$ (31,056)

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of Additional Information Regarding Stock Based Compensation

Certain information regarding our stock-based compensation was as follows (in thousands, except per share amounts):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020

Weighted average grant date per share fair value of RSUs granted	$	34.83	$	36.12	$	25.96
Total intrinsic value of stock options exercised	—		3,179		4,688
Fair value of RSUs vested	42,324		54,948		42,597

Schedule of Stock-based Compensation Expense

Pre-tax stock-based compensation expense by financial statement line and related tax benefit in the Consolidated Statements of Income are as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Stock-based compensation expense included in:
Cost of revenues	$	3,807	$	5,200	$	3,951
Research and development	8,217		7,583		5,824
Selling, general and administrative	19,313		16,601		14,055

Total stock-based compensation	$	31,337	$	29,384	$	23,830
Stock-based compensation tax benefit	$	2,772	$	6,118	$	4,962

Schedule of Unrecognized Compensation Expense

Unrecognized stock-based compensation expense at December 31, 2022 consisted of the following (in thousands):


	Unrecognized Expense		Weighted Average Recognition Period (Years)

Restricted stock units	$	45,726	2.1
Performance restricted stock units	12,216		2.0
Employee stock purchase plan	424		0.1
Total unrecognized stock-based compensation expense	$	58,366	2.1

Schedule of Assumptions, Fair Value of PRSUs

The following assumptions were used in estimating the fair value of PRSUs:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
PRSUs:
Dividend yield	—	%	—	%	—	%
Expected volatility	53.0	%	52.5	%	52.0	%
Risk-free interest rate	2.8	%	0.3	%	0.2	%
Expected life (in years)	2.9		2.9		2.8

Schedule of Assumptions, Fair Value of Employee Purchase Rights

The following assumptions were used in estimating the fair value of shares under the Employee Stock Purchase Plan:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Employee Stock Purchase Plan:
Dividend yield	—	%	—	%	—	%
Expected volatility	42.6% - 60.8%		33.6% - 74.4%		30.4% - 74.4%
Risk-free interest rate	0.1% - 3.0%		0.1% - 1.5%		0.1% - 1.5%
Expected life (in years)	0.5 - 1.0		0.5 - 1.0		0.5 - 1.0

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Current assets:
Cash and cash equivalents	$ 109,130	$ 151,010
Marketable securities	129,006	125,055
Accounts receivable, net	88,143	115,541
Inventories, net	123,157	111,548
Restricted cash	1,221	2,233
Prepaid expenses and other current assets	23,895	18,652
Total current assets	474,552	524,039
Restricted cash	2,631	2,099
Operating lease, right-of-use-assets	31,362	35,210
Property, plant and equipment, net	189,848	146,555
Goodwill	211,444	212,299
Intangibles, net	26,751	36,342
Deferred tax assets	67,646	61,995
Other assets	3,994	1,981
Total assets	1,008,228	1,020,520
Current liabilities:
Accounts payable	69,308	57,862
Accrued liabilities	42,115	50,836
Current portion of term loans, net of unamortized issuance cost of $5 and $5	1,045	8,931
Deferred revenue	29,846	23,224
Operating lease liabilities	7,353	7,901
Total current liabilities	149,667	148,754
Term loans, less current portion, net of unamortized issuance cost of $60 and $65	14,389	15,434
Deferred tax liabilities	2,732	3,623
Long-term operating lease liabilities	27,587	31,009
Other liabilities	5,568	5,920
Total liabilities	199,943	204,740
Stockholders’ equity:
Preferred stock	0	0
Common stock	77	78
Additional paid-in capital	844,842	898,945
Accumulated other comprehensive loss	(5,578)	(1,449)
Accumulated deficit	(31,056)	(81,794)
Total stockholders’ equity	808,285	815,780
Total liabilities and stockholders’ equity	$ 1,008,228	$ 1,020,520

Subsequent Events (Details) - Subsequent Event $ in Millions	1 Months Ended
	Jan. 31, 2023 USD ($)
Subsequent Event [Line Items]
Cash received from grant	$ 18.0
Grant performance obligation term	5 years

Income Taxes

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

Components of Income Before Income Taxes

The components of income before income taxes were as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
United States	$	30,047	$	74,298	$	72,950
Foreign	27,823		24,202		12,225
	$	57,870	$	98,500	$	85,175

Provision for Income Taxes

The components of the provision for income taxes are as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Current provision:
Federal	$	4,330	$	2,334	$	1,799
State	520		712		1,194
Foreign	8,625		7,661		4,278
	13,475		10,707		7,271
Deferred provision (benefit):
Federal	(5,886)		4,651		1,472
State	118		522		(267)
Foreign	(575)		(1,304)		(1,824)
	(6,343)		3,869		(619)
Total provision for income taxes	$	7,132	$	14,576	$	6,652

Tax Rate Reconciliation

The following is a reconciliation of the difference between income taxes computed by applying the federal statutory rate of 21% and the provision from income taxes (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
U.S. statutory federal tax rate	$	12,153	$	20,685	$	17,887
State taxes and credits, net of federal benefit	16		811		663
Stock-based compensation	(2,772)		(6,118)		(4,962)
Research and development credits	(8,264)		(7,153)		(6,576)
Foreign taxes at rates different than the U.S.	2,404		2,286		415
Other permanent differences	1,964		2,043		400
Global intangible low-taxed income	7		—		—
Foreign derived intangible income	(5,160)		(2,486)		(3,668)
Change in valuation allowance	2,597		2,231		1,862
Tax contingencies, net of reversals	3,124		2,812		2,712
Other	1,063		(535)		(2,081)
Total	$	7,132	$	14,576	$	6,652

Deferred Tax Assets and Liabilities

Deferred tax assets and liabilities are recognized for the future tax consequences of differences between the carrying amounts of assets and liabilities and their respective tax basis using enacted tax rates in effect for the year in which the differences are expected to be reversed.

Significant deferred tax assets and liabilities consisted of the following (in thousands):


	As of
	December 31, 2022		December 25, 2021
Tax credits	$	33,025	$	41,650
Inventory reserve	14,269		13,691
Other reserves and accruals	6,527		8,523
Non-statutory stock options	3,180		2,837
Lease liability	6,024		6,717
Research and development expenditures capitalization	36,821		19,553
Net operating loss carryforwards	18,173		18,395
Gross deferred tax assets	118,019		111,366
Valuation allowance	(43,295)		(40,698)
Total deferred tax assets	74,724		70,668
Right-of-use assets	(5,219)		(5,910)
Acquired intangibles and fixed assets	(4,342)		(6,163)
Unrealized investment gains	(103)		(105)
Tax on undistributed earnings	(146)		(118)
Total deferred tax liabilities	(9,810)		(12,296)
Net deferred tax assets	$	64,914	$	58,372

We are required to evaluate the realizability of our deferred tax assets in both our U.S. and non-U.S. jurisdictions on an ongoing basis to determine whether there is a need for a valuation allowance with respect to such deferred tax assets. As of December 31, 2022, we maintained a valuation allowance of $43.3 million, primarily related to California deferred tax assets and foreign tax credit carryovers, due to uncertainty about the future realization of these assets. We believe that future reversals of taxable temporary differences, and our forecast of continued earnings in both our U.S. and non-U.S. jurisdictions, support our decision to not record a valuation allowance on other deferred tax assets.

Tax Credits and Carryforwards

Tax credits and carryforwards available to us at December 31, 2022 consisted of the following (in thousands):


	Amount		Latest Expiration Date
Federal research and development tax credit	$	26,424	2034-2042
Foreign tax credit carryforwards	995		2023-2027
California research credits	52,131		Indefinite
State net operating loss carryforwards	249,087		2025-Indefinite
Singapore net operating loss carryforwards	5,724		Indefinite

Undistributed Earnings

As of December 31, 2022, unremitted earnings of foreign subsidiaries was estimated at $48.7 million. We intend to permanently invest $12.0 million of undistributed earnings indefinitely outside of the U.S. To the extent we repatriate the remaining $36.7 million of undistributed foreign earnings to the U.S., we established a deferred tax liability of $0.1 million for foreign withholding taxes. Our estimates are provisional and subject to change because of the complexity and variety of assumptions necessary to compute the tax.

Unrecognized Tax Benefits

We recognize the benefits of tax return positions if we determine that the positions are “more-likely-than-not” to be sustained by the taxing authority. Interest and penalties accrued on unrecognized tax benefits are recorded as tax expense in the period incurred.

The following table reflects changes in the unrecognized tax benefits (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Unrecognized tax benefit, beginning balance	$	35,745	$	32,497	$	28,800
Additions based on tax positions related to the current year	3,868		3,201		3,072
Additions based on tax positions from prior years	795		124		702
Reductions for tax positions of prior years	—		—		—
Reductions due to lapse of the applicable statute of limitations	(310)		(77)		(77)
Unrecognized tax benefit, ending balance	$	40,098	$	35,745	$	32,497

Interest and penalties recognized as a component of provision for income taxes	$	30	$	40	$	50
Interest and penalties accrued at period end	85		188		204

Of the unrecognized tax benefits at December 31, 2022, $20.2 million would impact the effective tax rate if recognized.

The amount of income taxes we pay is subject to ongoing audits by federal, state and foreign tax authorities which might result in proposed assessments. Our estimate for the potential outcome for any uncertain tax issue is judgmental in nature. However, we believe we have adequately provided for any reasonably foreseeable outcome related to those matters. Our future results may include favorable or unfavorable adjustments to our estimated tax liabilities in the period the assessments are made or resolved or when statutes of limitation on potential assessments expire. As of December 31, 2022, changes to our uncertain tax positions in the next 12 months that are reasonably possible are not expected to have a significant impact on our financial position or results of operations.

At December 31, 2022, our tax years 2019 through 2022, 2018 through 2022 and 2017 through 2022, remain open for examination in the federal, state and foreign jurisdictions, respectively. However, to the extent allowed by law, the taxing authorities may have the right to examine prior periods where net operating losses and credits were generated and carried forward, and make adjustments up to the net operating loss and credit carryforward amounts.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI https://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Accounting Policies [Abstract]
Aggregate inventory write downs	$ 24,632	$ 15,544	$ 13,117

Formation and Nature of Business	12 Months Ended
Formation and Nature of Business	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Formation and Nature of Business	Formation and Nature of Business FormFactor, Inc. was incorporated in Delaware on April 15, 1993 and is headquartered in Livermore, California. We are a leading provider of essential test and measurement technologies along the full semiconductor product lifecycle - from characterization, modeling, reliability, and design de-bug, to qualification and production test. We provide a broad range of high-performance probe cards, analytical probes, probe stations, metrology systems, thermal systems, and cryogenic systems to both semiconductor companies and scientific institutions. Our products provide electrical and physical information from a variety of semiconductor and electro-optical devices and integrated circuits from early research, through development, to high-volume production. Customers use our products and services to accelerate profitability by optimizing device performance and advancing yield knowledge. Design, development and manufacturing operations are located in Livermore, Carlsbad, and Baldwin Park, California; Beaverton, Oregon; Boulder, Colorado; and Woburn, Massachusetts, all in the United States; Bergisch Gladbach, Munich and Thiendorf, Germany, and sales, service and support operations are located in the United States, Germany, France, Italy, South Korea, Japan, Taiwan, China and Singapore. Fiscal Year Our fiscal year ends on the last Saturday in December. The fiscal years ended on December 31, 2022, December 25, 2021 and December 26, 2020 consisted of 53 weeks, 52 weeks and 52 weeks, respectively. The first three fiscal quarters in our fiscal year ended December 31, 2022 contained 13 weeks, and the fourth fiscal quarter contained 14 weeks.

Balance Sheet Components - Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	$ 131,251	$ 125,334
Gross Unrealized Gains	0	30
Gross Unrealized Losses	(2,245)	(309)
Fair Value	129,006	125,055
Amortized Cost
Due in one year or less	77,663	75,804
Due after one year to five years	53,588	49,530
Amortized Cost	131,251	125,334
Fair Value
Due in one year or less	76,902	75,778
Due after one year to five years	52,104	49,277
Fair Value	129,006	125,055
U.S. treasuries
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	25,498	39,128
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(479)	(143)
Fair Value	25,019	38,985
Amortized Cost
Amortized Cost	25,498	39,128
Fair Value
Fair Value	25,019	38,985
Commercial paper
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	24,893	32,174
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(53)	(13)
Fair Value	24,840	32,161
Amortized Cost
Amortized Cost	24,893	32,174
Fair Value
Fair Value	24,840	32,161
Corporate bonds
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	68,845	52,832
Gross Unrealized Gains	0	29
Gross Unrealized Losses	(1,449)	(151)
Fair Value	67,396	52,710
Amortized Cost
Amortized Cost	68,845	52,832
Fair Value
Fair Value	67,396	52,710
Certificates of deposit
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	720	1,200
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(14)	(2)
Fair Value	706	1,199
Amortized Cost
Amortized Cost	720	1,200
Fair Value
Fair Value	706	$ 1,199
U.S. agency securities
Debt Securities, Available-for-sale [Abstract]
Amortized Cost	11,295
Gross Unrealized Gains	0
Gross Unrealized Losses	(250)
Fair Value	11,045
Amortized Cost
Amortized Cost	11,295
Fair Value
Fair Value	$ 11,045

Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2022	Feb. 17, 2023	Jun. 24, 2022
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	000-50307
Entity Registrant Name	FormFactor, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-3711155
Entity Address, State or Province	7005 Southfront Road
Entity Address, City or Town	Livermore
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94551
City Area Code	925
Local Phone Number	290-4000
Title of 12(b) Security	Common stock, $0.001 par value
Trading Symbol	FORM
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 2,239.4
Entity Common Stock, Shares Outstanding (in shares)		77,140,504
Documents Incorporated by Reference	Portions of the registrant's definitive Proxy Statement for the 2023 Annual Meeting of Stockholders, which will be filed within 120 days of the end of the registrant's fiscal year ended December 31, 2022, are incorporated by reference in Part III hereof. Except with respect to information specifically incorporated by reference in this Annual Report on Form 10-K, the Proxy Statement is not deemed to be filed as a part of this Annual Report on Form 10-K.
Entity Central Index Key	0001039399
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY

Acquisition - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Jun. 09, 2022	Dec. 25, 2021	Dec. 26, 2020	Oct. 19, 2020	Jul. 30, 2020	Oct. 09, 2019
Business Acquisition [Line Items]
Goodwill	$ 211,444		$ 212,299	$ 212,761
Woburn
Business Acquisition [Line Items]
Accounts receivable		$ 178
Inventories		7,041
Property, plant and equipment		479
Prepaid expenses and other assets		117
Other asset		28
Tangible assets acquired		7,843
Deferred revenue		(5,513)
Accounts payable and accrued liabilities		(30)
Total net tangible assets acquired and liabilities assumed		2,300
Intangible assets		500
Goodwill		550
Net assets acquired		$ 3,350
High Precision Devices, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents					$ 1,680
Accounts receivable					1,017
Inventories					3,047
Property, plant and equipment					669
Operating lease, right-of-use-assets					2,554
Prepaid expenses and other assets					916
Tangible assets acquired					9,883
Deferred revenue					(2,529)
Accounts payable and accrued liabilities					(1,268)
Operating lease liabilities					(2,554)
Deferred tax liabilities					(2,400)
Total net tangible assets acquired and liabilities assumed					1,132
Intangible assets					11,520		$ 11,520
Goodwill					5,908
Net assets acquired					$ 18,560
Baldwin Park
Business Acquisition [Line Items]
Accounts receivable						$ 4,365
Inventories						2,727
Property, plant and equipment						9,053
Operating lease, right-of-use-assets						519
Prepaid expenses and other assets						56
Tangible assets acquired						16,720
Accounts payable and accrued liabilities						(743)
Operating lease liabilities						(519)
Total net tangible assets acquired and liabilities assumed						15,458
Intangible assets						13,600
Goodwill						5,942
Net assets acquired						$ 35,000

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Income Statement [Abstract]
Revenues	$ 747,937	$ 769,674	$ 693,616
Cost of revenues	451,928	446,907	405,696
Gross profit	296,009	322,767	287,920
Operating expenses:
Research and development	109,222	100,937	89,034
Selling, general and administrative	131,875	123,792	115,098
Total operating expenses	241,097	224,729	204,132
Operating income	54,912	98,038	83,788
Interest income	2,220	569	1,501
Interest expense	(579)	(602)	(864)
Other income, net	1,317	495	750
Income before income taxes	57,870	98,500	85,175
Provision for income taxes	7,132	14,576	6,652
Net income	$ 50,738	$ 83,924	$ 78,523
Net income per share:
Basic (in USD per share)	$ 0.65	$ 1.08	$ 1.02
Diluted (in USD per share)	$ 0.65	$ 1.06	$ 0.99
Weighted-average number of shares used in per share calculations:
Basic (in shares)	77,578	77,787	76,681
Diluted (in shares)	78,201	79,133	79,001

Summary of Significant Accounting Policies - Concentration of Credit Risk and Other Risks and Uncertainties (Details) - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Intel Corporation \| Revenue Benchmark
Concentration Risk [Line Items]
Concentration risk percentage	19.00%	20.40%	31.50%
Samsung Electronics Co., LTD. \| Revenue Benchmark
Concentration Risk [Line Items]
Concentration risk percentage		11.40%
Major Customer 1 \| Accounts Receivable
Concentration Risk [Line Items]
Concentration risk percentage	13.80%	13.80%

Segments and Geographic Information

12 Months Ended

Dec. 31, 2022

Segment Reporting [Abstract]

Segments and Geographic Information

We operate in two reportable segments consisting of the Probe Cards Segment and the Systems Segment.

Our chief operating decision maker (“CODM”) is our Chief Executive Officer, who reviews operating results to make decisions about allocating resources and assessing performance for the entire company.

The following table summarizes the operating results by reportable segment (dollars in thousands):


	Fiscal 2022
	Probe Cards			Systems			Corporate and Other		Total
Revenues	$	591,422		$	156,515		$	—	$	747,937
Gross profit	235,562			80,937			(20,490)		296,009
Gross margin	39.8		%	51.7		%			39.6		%


	Fiscal 2021
	Probe Cards			Systems			Corporate and Other		Total
Revenues	$	633,281		$	136,393		$	—	$	769,674
Gross profit	279,873			65,834			(22,940)		322,767
Gross margin	44.2		%	48.3		%			41.9		%


	Fiscal 2020
	Probe Cards			Systems			Corporate and Other		Total
Revenues	$	581,739		$	111,877		$	—	$	693,616
Gross profit	263,215			51,835			(27,130)		287,920
Gross margin	45.2		%	46.3		%			41.5		%

Operating results provide useful information to our management for assessment of our performance and results of operations. Certain components of our operating results are utilized to determine executive compensation along with other measures.

Corporate and Other includes unallocated expenses relating to amortization of intangible assets, share-based compensation expense, acquisition-related costs, including charges related to inventory and fixed assets stepped up to fair value, and other costs, which are not used in evaluating the results of, or in allocating resources to, our reportable segments. Acquisition-related costs include transaction costs and any costs directly related to the acquisition and integration of acquired businesses.

The following table summarizes revenue, by geographic region, as a percentage of total revenues based upon ship-to location:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Taiwan	22.7	%	24.2	%	21.7	%
China	21.5		21.2		25.2
United States	17.1		15.9		18.4
South Korea	14.9		16.0		12.5
Malaysia	6.7		6.4		1.6
Singapore	5.3		4.7		2.4
Europe	5.2		5.7		9.5
Japan	5.1		4.7		6.3
Rest of World	1.5		1.2		2.4
Total Revenues	100.0	%	100.0	%	100.0	%

The following table summarizes revenue by market (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Foundry & Logic	$	409,196	$	435,812	$	446,183
DRAM	133,446		156,049		109,734
Flash	48,780		41,420		25,822
Systems	156,515		136,393		111,877
Total revenues	$	747,937	$	769,674	$	693,616

The following table summarizes revenue by timing of revenue recognition (in thousands):


	Fiscal Year Ended
	December 31, 2022						December 25, 2021						December 26, 2020
	Probe Cards		Systems		Total		Probe Cards		Systems		Total		Probe Cards		Systems		Total
Products transferred at a point in time	$	587,738	$	144,456	$	732,194	$	630,038	$	124,788	$	754,826	$	579,569	$	104,858	$	684,427
Services transferred over time	3,684		12,059		15,743		3,243		11,605		14,848		2,170		7,019		9,189
Total	$	591,422	$	156,515	$	747,937	$	633,281	$	136,393	$	769,674	$	581,739	$	111,877	$	693,616

Long-lived assets, comprised of Operating lease, Right-of-use assets, Property, plant and equipment, net, Goodwill and Intangibles, net, reported based on the location of the asset was as follows (in thousands):


	December 31, 2022		December 25, 2021		December 26, 2020
United States	$	406,529	$	372,338	$	347,654
Europe	42,640		47,700		51,791
Asia-Pacific	10,236		10,368		7,322
Total	$	459,405	$	430,406	$	406,767

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Acquisition - Additional Information (Details) $ in Thousands					12 Months Ended
	Jun. 09, 2022 USD ($)	Oct. 19, 2020 USD ($) millikelvin	Jul. 30, 2020 USD ($)	Oct. 09, 2019	Dec. 31, 2022
Minimum
Business Acquisition [Line Items]
Weighted average useful life (in years)					1 year
Woburn
Business Acquisition [Line Items]
Total acquisition consideration	$ 3,400
Woburn \| Developed technologies
Business Acquisition [Line Items]
Weighted average useful life (in years)	3 years
High Precision Devices, Inc.
Business Acquisition [Line Items]
Total acquisition consideration		$ 16,900
Cash and cash equivalents		$ 1,680
Weighted average useful life (in years)				8 years 2 months 12 days
Percentage of voting interests acquired		100.00%
High Precision Devices, Inc. \| Developed technologies
Business Acquisition [Line Items]
Weighted average useful life (in years)				10 years
High Precision Devices, Inc. \| Minimum
Business Acquisition [Line Items]
Sensor markets, operating temperature \| millikelvin		30
Baldwin Park
Business Acquisition [Line Items]
Total acquisition consideration			$ 35,000
Weighted average useful life (in years)			7 years 8 months 12 days
Baldwin Park \| Developed technologies
Business Acquisition [Line Items]
Weighted average useful life (in years)			10 years

Derivative Financial Instruments - Interest Rate Swaps (Details) - USD ($) $ in Thousands			12 Months Ended
	Jun. 22, 2020	Mar. 17, 2020	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Building Term Loan
Derivative Instruments, Gain (Loss) [Line Items]
Debt instrument, interest rate, effective percentage		2.75%
Interest Rate Contract \| Building Term Loan
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount		$ 18,000	$ 18,000
Derivative, floor interest rate		0.00%
Derivative, floor interest rate term		1 year	1 year
Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in OCI/L on Derivative (Effective Portion)			$ 1,906	$ 451	$ (119)
Interest Rate Swap \| Other income, net \| Designated as Hedging Instrument \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI/L into Income (Effective Portion)			106	$ (154)	$ (64)
Senior Secured Term Loan
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount			$ 15,500
LIBOR \| Building Term Loan
Derivative Instruments, Gain (Loss) [Line Items]
Basis spread on variable rate	1.75%	1.75%	1.75%

Segments and Geographic Information - Revenue by Timing of Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	$ 747,937	$ 769,674	$ 693,616
Products transferred at a point in time
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	732,194	754,826	684,427
Services transferred over time
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	15,743	14,848	9,189
Probe Cards
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	591,422	633,281	581,739
Probe Cards \| Products transferred at a point in time
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	587,738	630,038	579,569
Probe Cards \| Services transferred over time
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	3,684	3,243	2,170
Systems
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	156,515	136,393	111,877
Systems \| Products transferred at a point in time
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	144,456	124,788	104,858
Systems \| Services transferred over time
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	$ 12,059	$ 11,605	$ 7,019

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 30
-Subparagraph (a)
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+ Details

Debt - Additional Information (Details) - USD ($)				12 Months Ended
Debt - Additional Information (Details) - USD ($)	Jun. 22, 2020	Mar. 17, 2020	Oct. 25, 2019	Dec. 31, 2022	Dec. 25, 2021
Debt Instrument [Line Items]
Term loans				$ 15,499,000	$ 24,435,000
FRT Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount			$ 23,400,000
Line of credit facility, expiration period			3 years
Long-term line of credit, quarterly repayment amount			$ 2,000,000
Building Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount	$ 18,000,000
Interest rate at period end				5.87%
Term loans				$ 15,500,000
Debt instrument, term	15 years
Debt instrument, interest payment term	15 years
Debt instrument, interest rate, effective percentage		2.75%
Building Term Loan \| Interest Rate Contract
Debt Instrument [Line Items]
Derivative, Notional Amount		$ (18,000,000)		$ (18,000,000)
Derivative, floor interest rate		0.00%
Derivative, floor interest rate term		1 year		1 year
LIBOR \| Building Term Loan
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%	1.75%		1.75%
Euro Interbank Offered Rate (EURIBOR) \| FRT Term Loan
Debt Instrument [Line Items]
Basis spread on variable rate			175.00%
Senior Secured Term Loan
Debt Instrument [Line Items]
Derivative, Notional Amount				$ (15,500,000)

Income Taxes - Undistributed Earnings (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Income Tax Contingency [Line Items]
Repatriation of earnings of foreign subsidiaries	$ 48,700
Deferred tax liabilities on undistributed earnings	146	$ 118
Non-US
Income Tax Contingency [Line Items]
Repatriation of earnings of foreign subsidiaries	12,000
United States
Income Tax Contingency [Line Items]
Repatriation of earnings of foreign subsidiaries	$ 36,700

Stockholders' Equity - Employee Stock Purchase Plan (Details)	12 Months Ended
	Dec. 31, 2022 purchasePeriod $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount from market price, offering date	85.00%
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)	7,000,000
Issuance of common stock under the Employee Stock Purchase Plan (in shares)	316,861
Weighted average exercise price, exercisable (in USD per share) \| $ / shares	$ 33.00
Weighted average discount (in USD per share) \| $ / shares	$ (6.13)
Shares available for grant (in shares)	1,476,211
Employee Stock \| Twelve Month
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period, duration	12 months
Number of purchase periods \| purchasePeriod	2
Purchase period, duration	6 months
Employee Stock \| Six Month
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period, duration	6 months
Number of purchase periods \| purchasePeriod	1
Purchase period, duration	6 months

Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Leases [Abstract]
Operating lease expense	$ 8,595	$ 8,485	$ 7,468
Short-term lease expense	385	180	136
Variable lease expense	2,393	1,842	1,574
Total lease expense	$ 11,373	$ 10,507	$ 9,178

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Debt Disclosure [Abstract]
Term loans	$ 15,499	$ 24,435
Less unamortized issuance costs	(65)	(70)
Term loans less issuance costs	$ 15,434	$ 24,365

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Summary of Significant Accounting Policies - Intangible Assets (Details)	12 Months Ended
	Dec. 31, 2022
Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life (in years)	1 year
Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life (in years)	10 years

Fair Value (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Schedule of Fair Values Measured on Recurring Basis


December 31, 2022	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	21,279	$	—	$	—	$	21,279

Commercial paper	—		4,969		—		4,969
U.S. agency securities	—		996		—		996
	21,279		5,965		—		27,244
Marketable securities:
U.S. treasuries	25,019		—		—		25,019
Certificates of deposit	—		706		—		706
U.S. agency securities	—		11,045		—		11,045
Corporate bonds	—		67,396		—		67,396
Commercial paper	—		24,840		—		24,840
	25,019		103,987		—		129,006
Foreign exchange derivative contracts	—		664		—		664
Promissory note receivable	—		—		943		943
Interest rate swap derivative contracts	—		2,374		—		2,374
Total assets	$	46,298	$	112,990	$	943	$	160,231
Liabilities:
Foreign exchange derivative contracts	$	—	$	(193)	$	—	$	(193)


Total liabilities	$	—	$	(193)	$	—	$	(193)


December 25, 2021	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	9,526	$	—	$	—	$	9,526
U.S. treasuries	2,500		—		—		2,500
Commercial paper	—		1,000		—		1,000
U.S. agency securities	—		5,556		—		5,556
	12,026		6,556		—		18,582
Marketable securities:
U.S. treasuries	38,985		—		—		38,985
Certificates of deposit	—		1,199		—		1,199

Corporate bonds	—		52,709		—		52,709
Commercial paper	—		32,162		—		32,162
	38,985		86,070		—		125,055

Interest rate swap derivative contracts	—		629		—		629
Total assets	$	51,011	$	93,255	$	—	$	144,266
Liabilities:
Foreign exchange derivative contracts	$	—	$	(489)	$	—	$	(489)
Interest rate swap derivative contracts	$	—	$	(55)	$	—	$	(55)

Total liabilities	$	—	$	(544)	$	—	$	(544)

Leases

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Leases

Our operating lease, right-of-use assets relate to real estate space under non-cancelable operating lease agreements for commercial and industrial space, as well as for our corporate headquarters located in Livermore, California. Our leases have remaining terms of 1 to 6 years, and some leases include options to extend up to 20 years. We also have operating leases for automobiles with remaining lease terms of 1 to 3 years. We did not include any of our renewal options in our lease terms for calculating our lease liability as the renewal options allow us to maintain operational flexibility and we are not reasonably certain we will exercise these options at this time. The weighted-average remaining lease term for our operating leases was 5.1 years at December 31, 2022 and the weighted-average discount rate was 3.84%.

The components of lease expense were as follows (in thousands):


	Lease Expense
	December 31, 2022		December 25, 2021		December 26, 2020
Operating lease expense	$	8,595	$	8,485	$	7,468
Short-term lease expense	385		180		136
Variable lease expense	2,393		1,842		1,574
	$	11,373	$	10,507	$	9,178

Future minimum payments under our non-cancelable operating leases were as follows as of December 31, 2022 (in thousands):


Fiscal Year	Amount
2023	$	8,038
2024	7,784
2025	7,695
2026	6,615
2027	5,737
Thereafter	3,423
Total minimum lease payments	39,292
Less: interest	(4,352)
Present value of net minimum lease payments	34,940
Less: current portion	(7,353)
Total long-term operating lease liabilities	$	27,587

Leases - Narrative (Details)	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Operating lease, renewal term	20 years
Operating lease, weighted average remaining lease term	5 years 1 month 6 days
Operating lease, weighted average discount rate	3.84%
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, term of contract	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, term of contract	6 years
Automobiles \| Minimum
Lessee, Lease, Description [Line Items]
Operating lease, term of contract	1 year
Automobiles \| Maximum
Lessee, Lease, Description [Line Items]
Operating lease, term of contract	3 years

Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restructuring and impairment charges, net	$ 31,337	$ 29,384	$ 23,830
Stock-based compensation tax benefit	2,772	6,118	4,962
Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restructuring and impairment charges, net	3,807	5,200	3,951
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restructuring and impairment charges, net	8,217	7,583	5,824
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restructuring and impairment charges, net	$ 19,313	$ 16,601	$ 14,055

Segments and Geographic Information - Revenue by Country (Details) - Geographic Concentration Risk - Revenue	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Product Information [Line Items]
Concentration risk percentage	100.00%	100.00%	100.00%
Taiwan
Product Information [Line Items]
Concentration risk percentage	22.70%	24.20%	21.70%
China
Product Information [Line Items]
Concentration risk percentage	21.50%	21.20%	25.20%
United States
Product Information [Line Items]
Concentration risk percentage	17.10%	15.90%	18.40%
South Korea
Product Information [Line Items]
Concentration risk percentage	14.90%	16.00%	12.50%
Malaysia
Product Information [Line Items]
Concentration risk percentage	6.70%	6.40%	1.60%
Singapore
Product Information [Line Items]
Concentration risk percentage	5.30%	4.70%	2.40%
Europe
Product Information [Line Items]
Concentration risk percentage	5.20%	5.70%	9.50%
Japan
Product Information [Line Items]
Concentration risk percentage	5.10%	4.70%	6.30%
Rest of World
Product Information [Line Items]
Concentration risk percentage	1.50%	1.20%	2.40%

Fair Value - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	$ 27,244	$ 18,582
Marketable securities:	129,006	125,055
Total assets	160,231	144,266
Liabilities measured at fair value	(193)	(544)
Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	664
Derivative liability	(193)	(489)
Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	2,374	629
Derivative liability		(55)
Promissory note receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	943
Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	21,279	9,526
U.S. treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		2,500
Marketable securities:	25,019	38,985
Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities:	706	1,199
U.S. agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	996
Marketable securities:	11,045
Corporate bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		5,556
Marketable securities:	67,396	52,709
Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	4,969	1,000
Marketable securities:	24,840	32,162
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	21,279	12,026
Marketable securities:	25,019	38,985
Total assets	46,298	51,011
Liabilities measured at fair value	0	0
Level 1 \| Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0
Derivative liability	0	0
Level 1 \| Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0	0
Derivative liability		0
Level 1 \| Promissory note receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0
Level 1 \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	21,279	9,526
Level 1 \| U.S. treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		2,500
Marketable securities:	25,019	38,985
Level 1 \| Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities:	0	0
Level 1 \| U.S. agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0
Marketable securities:	0
Level 1 \| Corporate bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		0
Marketable securities:	0	0
Level 1 \| Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0	0
Marketable securities:	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	5,965	6,556
Marketable securities:	103,987	86,070
Total assets	112,990	93,255
Liabilities measured at fair value	(193)	(544)
Level 2 \| Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	664
Derivative liability	(193)	(489)
Level 2 \| Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	2,374	629
Derivative liability		(55)
Level 2 \| Promissory note receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0
Level 2 \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0	0
Level 2 \| U.S. treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		0
Marketable securities:	0	0
Level 2 \| Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities:	706	1,199
Level 2 \| U.S. agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	996
Marketable securities:	11,045
Level 2 \| Corporate bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		5,556
Marketable securities:	67,396	52,709
Level 2 \| Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	4,969	1,000
Marketable securities:	24,840	32,162
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0	0
Marketable securities:	0	0
Total assets	943	0
Liabilities measured at fair value	0	0
Level 3 \| Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0
Derivative liability	0	0
Level 3 \| Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0	0
Derivative liability		0
Level 3 \| Promissory note receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	943
Level 3 \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0	0
Level 3 \| U.S. treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:		0
Marketable securities:	0	0
Level 3 \| Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities:	0	0
Level 3 \| U.S. agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0	0
Marketable securities:	0
Level 3 \| Corporate bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities:	0	0
Level 3 \| Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents:	0	0
Marketable securities:	$ 0	$ 0

Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Current provision:
Federal	$ 4,330	$ 2,334	$ 1,799
State	520	712	1,194
Foreign	8,625	7,661	4,278
Total current provision (benefit)	13,475	10,707	7,271
Deferred provision (benefit):
Federal	(5,886)	4,651	1,472
State	118	522	(267)
Foreign	(575)	(1,304)	(1,824)
Total deferred provision (benefit)	(6,343)	3,869	(619)
Total provision for income taxes	$ 7,132	$ 14,576	$ 6,652

Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2022

Balance Sheet Components [Abstract]

Schedule of Marketable Securities

Marketable securities consisted of the following (in thousands):


December 31, 2022	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. treasuries	$	25,498	$	—	$	(479)	$	25,019
Commercial paper	24,893		—		(53)		24,840
Corporate bonds	68,845		—		(1,449)		67,396
Certificate of deposit	720		—		(14)		706
U.S. agency securities	11,295		—		(250)		11,045
	$	131,251	$	—	$	(2,245)	$	129,006


December 25, 2021	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. treasuries	$	39,128	$	—	$	(143)	$	38,985
Commercial paper	32,174		—		(13)		32,161
Corporate bonds	52,832		29		(151)		52,710
Certificate of deposit	1,200		1		(2)		1,199

	$	125,334	$	30	$	(309)	$	125,055

Contractual Maturity of Marketable Securities

The contractual maturities of marketable securities were as follows (in thousands):


	December 31, 2022				December 25, 2021
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in one year or less	$	77,663	$	76,902	$	75,804	$	75,778
Due after one year to five years	53,588		52,104		49,530		49,277
	$	131,251	$	129,006	$	125,334	$	125,055

Schedule of Net Inventory

Inventories consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Raw materials	$	55,726	$	57,673
Work-in-progress	46,067		35,935
Finished goods	21,364		17,940
	$	123,157	$	111,548

Schedule of Property, Plant and Equipment

Property, plant and equipment, net consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Land	$	17,136	$	4,751
Building and building improvements	44,932		41,722
Machinery and equipment	276,180		252,632
Computer equipment and software	45,813		44,667
Furniture and fixtures	7,540		7,293
Leasehold improvements	86,500		82,266
Sub-total	478,101		433,331
Less: Accumulated depreciation and amortization	(335,711)		(312,700)
Net property, plant and equipment	142,390		120,631
Construction-in-progress	47,458		25,924
Total	$	189,848	$	146,555

Schedule of Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Accrued compensation and benefits	$	15,864	$	29,706
Accrued income and other taxes	12,817		8,086
Accrued employee stock purchase plan contributions withheld	4,585		4,693
Accrued warranty	4,199		2,805
Accrued restructuring charges	1,249		2,478

Other accrued expenses	3,401		3,068
	$	42,115	$	50,836

Segments and Geographic Information (Tables)

12 Months Ended

Dec. 31, 2022

Segment Reporting [Abstract]

Operating Results by Reportable Segments

The following table summarizes the operating results by reportable segment (dollars in thousands):


	Fiscal 2022
	Probe Cards			Systems			Corporate and Other		Total
Revenues	$	591,422		$	156,515		$	—	$	747,937
Gross profit	235,562			80,937			(20,490)		296,009
Gross margin	39.8		%	51.7		%			39.6		%


	Fiscal 2021
	Probe Cards			Systems			Corporate and Other		Total
Revenues	$	633,281		$	136,393		$	—	$	769,674
Gross profit	279,873			65,834			(22,940)		322,767
Gross margin	44.2		%	48.3		%			41.9		%


	Fiscal 2020
	Probe Cards			Systems			Corporate and Other		Total
Revenues	$	581,739		$	111,877		$	—	$	693,616
Gross profit	263,215			51,835			(27,130)		287,920
Gross margin	45.2		%	46.3		%			41.5		%

Summary of Revenue by Geographic Region

The following table summarizes revenue, by geographic region, as a percentage of total revenues based upon ship-to location:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Taiwan	22.7	%	24.2	%	21.7	%
China	21.5		21.2		25.2
United States	17.1		15.9		18.4
South Korea	14.9		16.0		12.5
Malaysia	6.7		6.4		1.6
Singapore	5.3		4.7		2.4
Europe	5.2		5.7		9.5
Japan	5.1		4.7		6.3
Rest of World	1.5		1.2		2.4
Total Revenues	100.0	%	100.0	%	100.0	%

Summary of Revenue by Market

The following table summarizes revenue by market (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Foundry & Logic	$	409,196	$	435,812	$	446,183
DRAM	133,446		156,049		109,734
Flash	48,780		41,420		25,822
Systems	156,515		136,393		111,877
Total revenues	$	747,937	$	769,674	$	693,616

Summary of Revenue by Timing of Recognition

The following table summarizes revenue by timing of revenue recognition (in thousands):


	Fiscal Year Ended
	December 31, 2022						December 25, 2021						December 26, 2020
	Probe Cards		Systems		Total		Probe Cards		Systems		Total		Probe Cards		Systems		Total
Products transferred at a point in time	$	587,738	$	144,456	$	732,194	$	630,038	$	124,788	$	754,826	$	579,569	$	104,858	$	684,427
Services transferred over time	3,684		12,059		15,743		3,243		11,605		14,848		2,170		7,019		9,189
Total	$	591,422	$	156,515	$	747,937	$	633,281	$	136,393	$	769,674	$	581,739	$	111,877	$	693,616

Long-lived Assets by Location


	December 31, 2022		December 25, 2021		December 26, 2020
United States	$	406,529	$	372,338	$	347,654
Europe	42,640		47,700		51,791
Asia-Pacific	10,236		10,368		7,322
Total	$	459,405	$	430,406	$	406,767

Balance Sheet Components - Property Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 478,101	$ 433,331
Less: Accumulated depreciation and amortization	(335,711)	(312,700)
Net property, plant and equipment	142,390	120,631
Construction-in-progress	47,458	25,924
Total	189,848	146,555
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	17,136	4,751
Building and building improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	44,932	41,722
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	276,180	252,632
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	45,813	44,667
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	7,540	7,293
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 86,500	$ 82,266

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Cash flows from operating activities:
Net income	$ 50,738	$ 83,924	$ 78,523
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	28,646	25,772	20,694
Amortization	9,391	18,747	27,991
Amortization (accretion) of discount on investments	182	403	(2)
Reduction in the carrying amount of right-of-use assets	8,153	7,172	5,955
Stock-based compensation expense	31,337	29,384	23,830
Deferred income tax provision (benefit)	(6,343)	3,869	(562)
Provision for excess and obsolete inventories	24,632	15,544	13,117
Acquired inventory step-up amortization	476	723	838
Loss on disposal of long-lived assets	296	449	451
Non-cash restructuring charges	200	1,646	0
Gain on contingent consideration	0	(95)	(2,879)
Foreign currency transaction losses (gains)	2,251	1,582	(936)
Loss on derivative instruments	0	0	372
Changes in assets and liabilities:
Accounts receivable	26,028	(9,086)	(3,545)
Inventories	(28,780)	(31,655)	(22,191)
Prepaid expenses and other current assets	(4,591)	3,808	(6,207)
Other assets	66	(326)	179
Accounts payable	3,899	(6,589)	16,788
Accrued liabilities	(8,002)	(725)	13,892
Other liabilities	(63)	285	362
Deferred revenues	1,286	1,974	8,901
Operating lease liabilities	(8,016)	(7,442)	(6,315)
Net cash provided by operating activities	131,786	139,364	169,256
Cash flows from investing activities:
Acquisition of property, plant and equipment	(65,254)	(66,496)	(55,865)
Acquisition of business, net of cash acquired	(3,350)	0	(51,880)
Proceeds from sale of subsidiary	0	0	82
Purchase of promissory note receivable	(1,000)	0	0
Purchases of marketable securities	(101,894)	(149,979)	(51,224)
Proceeds from maturities of marketable securities	95,794	91,734	59,965
Net cash used in investing activities	(75,704)	(124,741)	(98,922)
Cash flows from financing activities:
Proceeds from issuances of common stock	10,499	10,653	10,010
Purchase of common stock through stock repurchase program	(82,328)	(24,038)	0
Tax withholdings related to net share settlements of equity awards	(15,705)	(20,604)	(15,450)
Proceeds from term loan	0	0	18,000
Payments on term loan	(8,398)	(9,337)	(43,417)
Payment of term loan issuance costs	0	0	(78)
Payment of contingent consideration	0	3,873	0
Net cash used in financing activities	(95,932)	(47,199)	(30,935)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(2,510)	(3,180)	3,762
Net increase (decrease) in cash, cash equivalents and restricted cash	(42,360)	(35,756)	43,161
Cash, cash equivalents and restricted cash, beginning of year	155,342	191,098	147,937
Cash, cash equivalents and restricted cash, end of year	112,982	155,342	191,098
Supplemental disclosure of non-cash investing and financing activities:
Operating lease, right-of-use assets obtained in exchange for lease obligations	4,975	12,254	1,912
Increase in accounts payable and accrued liabilities related to property, plant and equipment purchases	7,469	2,711	2,545
Supplemental disclosure of cash flow information:
Income taxes paid, net	10,917	7,957	9,150
Cash paid for interest, net	535	643	867
Operating cash outflows from operating leases	8,913	8,520	7,546
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	109,130	151,010	187,225
Restricted cash, current	1,221	2,233	1,904
Restricted cash	2,631	2,099	1,969
Total cash, cash equivalents and restricted cash	$ 112,982	$ 155,342	$ 191,098

Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Components of Deferred Tax Assets and Liabilities [Abstract]
Tax credits	$ 33,025	$ 41,650
Inventory reserve	14,269	13,691
Other reserves and accruals	6,527	8,523
Non-statutory stock options	3,180	2,837
Lease liability	6,024	6,717
Research and development expenditures capitalization	36,821	19,553
Net operating loss carryforwards	18,173	18,395
Gross deferred tax assets	118,019	111,366
Valuation allowance	(43,295)	(40,698)
Total deferred tax assets	74,724	70,668
Right-of-use assets	(5,219)	(5,910)
Acquired intangibles and fixed assets	(4,342)	(6,163)
Unrealized investment gains	(103)	(105)
Tax on undistributed earnings	(146)	(118)
Total deferred tax liabilities	(9,810)	(12,296)
Net deferred tax assets	$ 64,914	$ 58,372

Segments and Geographic Information - Revenue by Market (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Revenue from External Customers [Line Items]
Revenues	$ 747,937	$ 769,674	$ 693,616
Foundry & Logic
Revenue from External Customers [Line Items]
Revenues	409,196	435,812	446,183
DRAM
Revenue from External Customers [Line Items]
Revenues	133,446	156,049	109,734
Flash
Revenue from External Customers [Line Items]
Revenues	48,780	41,420	25,822
Systems
Revenue from External Customers [Line Items]
Revenues	$ 156,515	$ 136,393	$ 111,877

- Definition

+ References

+ Details

Fair Value - Narrative (Details) - USD ($)	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets (liabilities), net	$ 0	$ 0	$ 0

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Schedule of Allowance for Doubtful Accounts

Activity related to our allowance for credit losses was as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Balance at beginning of year	$	195	$	248	$	222
Charges (reversals) to costs and expenses	(27)		(53)		26
Balance at end of year	$	168	$	195	$	248

Schedules of Concentration of Risk, by Customer

The following customers represented 10% or more of our revenues:


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Intel Corporation	19.0	%	20.4	%	31.5	%
Samsung Electronics Co., LTD.	*		11.4		*

* Less than 10% of revenues.

Schedule of Product Warranty Liability Reconciliation

A reconciliation of the changes in our warranty liability is as follows (in thousands):


	Fiscal Year Ended
	December 31, 2022		December 25, 2021		December 26, 2020
Balance at beginning of year	$	2,805	$	3,918	$	1,942
Accruals	7,746		5,759		5,727
Settlements	(6,352)		(6,872)		(3,751)
Balance at end of year	$	4,199	$	2,805	$	3,918

Schedule of Calculation of Numerator and Denominator in Earnings Per Share

The following table reconciles the shares used in calculating basic net income per share and diluted net income per share (in thousands):


	Fiscal Year Ended
	December 31, 2022	December 25, 2021	December 26, 2020



Weighted-average shares used in computing basic net income per share	77,578	77,787	76,681
Add potentially dilutive securities	623	1,346	2,320
Weighted-average shares used in computing basic and diluted net income per share	78,201	79,133	79,001

Schedule of Accumulated Other Comprehensive Income (Loss)


	December 31, 2022		December 25, 2021
Unrealized losses on available-for-sale marketable securities and other investments	$	(2,749)	$	(724)
Translation adjustments	(5,675)		(811)
Unrealized gains on derivative instruments	2,846		86
Accumulated other comprehensive loss	$	(5,578)	$	(1,449)

Stockholders' Equity - Common Stock and Repurchase Program (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	May 20, 2022	Oct. 26, 2020
Class of Stock [Line Items]
Dividends declared and paid	$ 0
Stock repurchased during the period, amount	$ 82,328,000	$ 24,038,000
Common Stock \| 2020 Share Repurchase Program
Class of Stock [Line Items]
Stock repurchase program authorized amount				$ 50,000,000
Stock repurchased during the period (in shares)	676,408	622,400
Stock repurchased during the period, amount	$ 26,000,000	$ 24,000,000
Common Stock \| 2022 Share Repurchase Program
Class of Stock [Line Items]
Stock repurchase program authorized amount			$ 75,000,000
Stock repurchased during the period (in shares)	1,700,893
Stock repurchased during the period, amount	$ 56,400,000
Remaining available for future repurchases	$ 18,600,000

Summary of Significant Accounting Policies - Net Income per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Accounting Policies [Abstract]
Weighted-average shares used in computing basic net income (loss) per share (in shares)	77,578	77,787	76,681
Add potentially dilutive securities (in shares)	623	1,346	2,320
Weighted-average shares used in computing basic and diluted net income per share (in shares)	78,201	79,133	79,001

Leases (Tables)

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Components of Lease Expense

The components of lease expense were as follows (in thousands):


	Lease Expense
	December 31, 2022		December 25, 2021		December 26, 2020
Operating lease expense	$	8,595	$	8,485	$	7,468
Short-term lease expense	385		180		136
Variable lease expense	2,393		1,842		1,574
	$	11,373	$	10,507	$	9,178

Schedule of Future Minimum Payments

Future minimum payments under our non-cancelable operating leases were as follows as of December 31, 2022 (in thousands):


Fiscal Year	Amount
2023	$	8,038
2024	7,784
2025	7,695
2026	6,615
2027	5,737
Thereafter	3,423
Total minimum lease payments	39,292
Less: interest	(4,352)
Present value of net minimum lease payments	34,940
Less: current portion	(7,353)
Total long-term operating lease liabilities	$	27,587

Derivative Financial Instruments - Foreign Currency Derivatives (Details) - 12 months ended Dec. 31, 2022 € in Thousands, ₩ in Thousands, ¥ in Thousands, $ in Thousands	USD ($)	EUR (€)	JPY (¥)	KRW (₩)
Derivatives, Fair Value [Line Items]
Cash flow hedge amount to be reclassified within twelve months	$ 500
Buy \| Euro \| Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Derivative, notional amount	(22,615)	€ (21,576)
Buy \| Korean Won \| Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Derivative, notional amount	(1,639)			₩ (2,067,724)
Sell \| Euro \| Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Derivative, notional amount	(5,107)	€ (4,927)
Sell \| Japanese Yen \| Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Derivative, notional amount	(22,906)		¥ (2,989,654)
Sell \| Taiwan Dollar \| Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Derivative, notional amount	$ (1,397)		¥ (42,826)

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases See Note 6, Leases. Environmental Matters We are subject to U.S. federal, state, local, and foreign governmental laws and regulations relating to the protection of the environment, including those governing the discharge of pollutants into the air and water, the management and disposal of hazardous substances and wastes, the clean-up of contaminated sites and the maintenance of a safe workplace. We believe that we comply in all material respects with the environmental laws and regulations that apply to us as of December 31, 2022. There are no matters pending that we currently believe are reasonably possible of having a material impact to our business, consolidated financial condition, results of operations or cash flows. In the future, we may receive notices of violations of environmental regulations, or otherwise learn of such violations. Environmental contamination or violations may negatively impact our business. Indemnification Arrangements We have entered, and may from time to time in the ordinary course of our business enter, into contractual arrangements with third parties that include indemnification obligations. Under these contractual arrangements, we have agreed to defend, indemnify and/or hold the third party harmless from and against certain liabilities. These arrangements include indemnities in favor of customers in the event that our products or services infringe a third party's intellectual property, or cause property damage or other indemnities in favor of our lessors in connection with facility leasehold liabilities that we may cause. In addition, we have entered into indemnification agreements with our directors and certain of our officers, and our bylaws contain indemnification obligations in favor of our directors, officers and agents. These indemnity arrangements may limit the type of the claim, the total amount that we can be required to pay in connection with the indemnification obligation and the time within which an indemnification claim can be made. The duration of the indemnification obligation may vary, and for most arrangements, survives the agreement term and is indefinite. We believe that substantially all of our indemnity arrangements provide either for limitations on the maximum potential future payments we could be obligated to make, or for limitations on the types of claims and damages we could be obligated to indemnify, or both. However, it is not possible to determine or reasonably estimate the maximum potential amount of future payments under these indemnification obligations due to the varying terms of such obligations, a lack of history of prior indemnification claims, the unique facts and circumstances involved in each particular contractual arrangement and in each potential future claim for indemnification, and the contingency of any potential liabilities upon the occurrence of events that are not reasonably determinable. We have not had any material requests for indemnification under these arrangements. We have not recorded any liabilities for these indemnification arrangements on our Consolidated Balance Sheets as of December 31, 2022 or December 25, 2021. Legal Matters From time to time, we may be subject to legal proceedings and claims in the ordinary course of business. As of December 31, 2022, and as of the filing of these financial statements, we were not involved in any material legal proceedings. In the future, we may become a party to additional legal proceedings that may require us to spend significant resources. Litigation can be expensive and disruptive to normal business operations. The results of legal proceedings are difficult to predict, and the costs incurred in litigation can be substantial, regardless of outcome.

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2022
Audit Information [Abstract]
Auditor Name	KPMG, LLP
Auditor Location	Portland, Oregon
Auditor Firm ID	185

Restructuring Charges - Restructuring Costs by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 15,586	$ 5,621
Cost of revenues
Restructuring Cost and Reserve [Line Items]
Restructuring charges	11,775	3,205
Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,498	869
Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2,166	$ 50

Goodwill and Intangible Assets - Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Property, Plant and Equipment [Line Items]
Amortization of intangible assets	$ 9,391	$ 18,747	$ 27,991
Finite-Lived Intangible Assets, Net, Amortization Expense, Rolling Maturity [Abstract]
2023	7,166
2024	4,584
2025	4,243
2026	3,155
2027	2,816
Thereafter	4,387
Total	26,351
Cost of revenues
Property, Plant and Equipment [Line Items]
Amortization of intangible assets	3,225	12,269	21,609
Selling, general and administrative
Property, Plant and Equipment [Line Items]
Amortization of intangible assets	$ 6,166	$ 6,478	$ 6,382

Debt (Tables)

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Schedule of Debt

Our debt consisted of the following (in thousands):


	December 31, 2022		December 25, 2021
Term loans	$	15,499	$	24,435
Less unamortized issuance costs	(65)		(70)
Term loans less issuance costs	$	15,434	$	24,365

Schedule of Maturities of Long-term Debt

Future principal and interest payments on our term loans as of December 31, 2022, based on the interest rate in effect at that date were as follows (in thousands):


	Payments Due In Fiscal Year
	2023		2024		2025		2026		2027		2028 and thereafter		Total
Term loans - principal payments	$	1,050	$	1,080	$	1,111	$	1,142	$	1,175	$	9,941	$	15,499
Term loans - interest payments(1)	894		835		763		699		630		2,324		6,145
	$	1,944	$	1,915	$	1,874	$	1,841	$	1,805	$	12,265	$	21,644

(1) Represents our minimum interest payment commitment at 5.87% per annum for the Building Term Loan, excluding the interest rate swap described above.

Leases - Schedule of Future Minimum Payments Under Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Leases [Abstract]
2023	$ 8,038
2024	7,784
2025	7,695
2026	6,615
2027	5,737
Thereafter	3,423
Total minimum lease payments	39,292
Less: interest	(4,352)
Present value of net minimum lease payments	34,940
Less: current portion	(7,353)	$ (7,901)
Long-term operating lease liabilities	$ 27,587	$ 31,009

Summary of Significant Accounting Policies - Warranty Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of year	$ 2,805	$ 3,918	$ 1,942
Accruals	7,746	5,759	5,727
Settlements	(6,352)	(6,872)	(3,751)
Balance at end of year	$ 4,199	$ 2,805	$ 3,918

Stockholders' Equity

12 Months Ended

Dec. 31, 2022

Equity [Abstract]

Stockholders' Equity

Preferred Stock

We have authorized 10,000,000 shares of undesignated preferred stock, $0.001 par value, none of which is issued and outstanding. Our Board of Directors shall determine the rights, preferences, privileges and restrictions of the preferred stock, including dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of any series.

Common Stock

Each share of common stock has the right to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Board of Directors, subject to the prior rights of holders, if any, of all classes of stock outstanding having priority rights as to dividends. No dividends have been declared or paid as of December 31, 2022.

Common Stock Repurchase Programs

On October 26, 2020, our Board of Directors authorized a two-year program to repurchase up to $50 million of outstanding common stock to offset potential dilution from issuances of common stock under our stock-based compensation programs. During fiscal 2020, we did not repurchase any shares. During fiscal 2021 we repurchased and retired 622,400 shares of common stock for $24.0 million, and as of December 31, 2022 we had utilized the remaining funds available for repurchase under this program after repurchasing 676,408 shares of common stock for $26.0 million during fiscal 2022.

On May 20, 2022, our Board of Directors authorized an additional program to repurchase up to $75 million of outstanding common stock, also with the primary purpose of offsetting potential dilution from issuance of common stock under our stock-based compensation programs. This share repurchase program will expire on May 20, 2024. During fiscal 2022, we repurchased and retired 1,700,893 shares of common stock for $56.4 million and as of December 31, 2022 $18.6 million remained available for future repurchases.

Equity Incentive Plan

We currently grant equity-based awards under our Equity Incentive Plan, as amended (the “2012 Plan”) which was approved by our stockholders. As amended, the 2012 Plan has authorized for issuance a total of 27.4 million shares, 6.5 million of which were available for grant as of December 31, 2022.

Restricted stock units (“RSUs”) granted under the 2012 Plan generally vest over three years in annual tranches, though we have granted, and will continue to grant, such awards that vest over a shorter term for employee retention purposes. RSUs, including Performance Restricted Stock Units (“PRSUs”) are converted into shares of our common stock upon vesting on a one-for-one basis. The vesting of RSUs is subject to the employee's continuing service.

RSU activity was as follows:


	Number of Shares	Weighted Average Grant Date Fair Value
Restricted stock units at December 25, 2021	2,166,934	$	28.63
Granted	1,356,948	34.83
Vested	(1,156,130)	22.60
Canceled	(140,671)	32.73
Restricted stock units at December 31, 2022	2,227,081	35.28

The PRSUs granted in fiscal 2022, 2021 and 2020 listed below vest based on us achieving certain market performance criteria. The performance criteria are based on a metric called Total Shareholder Return (“TSR”) for the performance period of three years, relative to the TSR of the companies identified as being part of the S&P Semiconductor Select Industry Index (FormFactor peer companies) as of a specific date.

Of the 273,000 PRSUs granted in fiscal 2019, 36,000 shares were forfeited, resulting in 237,000 shares vesting in fiscal 2022. These shares achieved 147% TSR performance, which resulted in an additional 110,605 shares issued during fiscal 2022 related to the 2019 PRSU grant.

PRSU grant activity was as follows:

Fiscal Year Ended

December 31, 2022

December 25, 2021

December 26, 2020

Grant Date

August 1, 2022

August 2, 2021

August 27, 2020

Performance period

July 1, 2022 - June 30, 2025

July 1, 2021 - June 30, 2024

July 1, 2020 - June 30, 2023

Number of shares

204,903

197,128

258,000

TSR as-of date

August 1, 2022

August 2, 2021

August 27, 2020

Stock-based compensation

$8.6 million

$6.9 million

Employee Stock Purchase Plan

Our 2012 Employee Stock Purchase Plan (the “ESPP”), as amended, allows for the issuance of a total of 7,000,000 shares. The offering periods under the ESPP are 12 months commencing on February 1 of each calendar year and ending on January 31 of the subsequent calendar year, and a six-month fixed offering period commencing on August 1 of each calendar year and ending on January 31 of the subsequent calendar year. The 12-month offering period consists of two six-month purchase periods and the six-month offering period consists of one six-month purchase period. The price of the common stock purchased is 85% of the lesser of the fair market value of the common stock on the first day of the applicable offering period or the last day of each purchase period. We have treated the 2012 ESPP as a compensatory plan.

During fiscal 2022, employees purchased 316,861 shares under this program at a weighted average exercise price of $33.00 per share, which represented a weighted average discount of $6.13 per share from the fair value of the stock purchased. As of December 31, 2022, 1,476,211 shares remained available for issuance.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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+ Details

Summary of Significant Accounting Policies - Property, Plant, and Equipment (Details)	12 Months Ended
	Dec. 31, 2022
Machinery and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	3 years
Machinery and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	5 years
Computer equipment and software \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	3 years
Computer equipment and software \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	5 years
Furniture and fixtures \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	3 years
Furniture and fixtures \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	5 years
Building and building improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	30 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment useful lives	7 years

Stockholders' Equity - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Granted (in USD per share)	$ 34.83	$ 36.12	$ 25.96
Restructuring and impairment charges, net	$ 31,337	$ 29,384	$ 23,830
Performance Restricted Stock Units
Number of Shares
Number of Shares, Granted (in shares)	204,903	197,128	258,000
Weighted Average Grant Date Fair Value
Performance period	3 years
Stock options granted (in shares)	204,903	197,128	258,000
Restructuring and impairment charges, net	$ 8,600	$ 8,600	$ 6,900
2012 Plan
Number of Shares
Number of Shares, Granted (in shares)				273,000
Weighted Average Grant Date Fair Value
Stock options granted (in shares)				273,000
2012 Plan \| Restricted stock units
Number of Shares
Number of Shares, Restricted stock units, beginning balance (in shares)	2,166,934
Number of Shares, Granted (in shares)	1,356,948
Number of Shares, Vested (in shares)	(1,156,130)
Number of Shares, Canceled (in shares)	(140,671)
Number of Shares, Restricted stock units, ending balance (in shares)	2,227,081	2,166,934
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Restricted stock units, beginning balance (in USD per share)	$ 28.63
Weighted Average Grant Date Fair Value, Granted (in USD per share)	34.83
Weighted Average Grant Date Fair Value, Vested (in USD per share)	22.60
Weighted Average Grant Date Fair Value, Canceled (in USD per share)	32.73
Weighted Average Grant Date Fair Value, Restricted stock units, ending balance (in USD per share)	$ 35.28	$ 28.63
Stock options granted (in shares)	1,356,948
2019 PRSU Grant
Number of Shares
Number of Shares, Granted (in shares)	110,605,000
Weighted Average Grant Date Fair Value
Stock options granted (in shares)	110,605,000
TSR performance (percent)	147.00%
2019 PRSU Grant \| Performance Restricted Stock Units
Number of Shares
Number of Shares, Vested (in shares)	(237,000)
Number of Shares, Canceled (in shares)	(36,000)

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2022
Accounting Policies [Abstract]
Fiscal Year	Fiscal YearOur fiscal year ends on the last Saturday in December.
Basis of Consolidation and Foreign Currency Translation	Basis of Consolidation and Foreign Currency TranslationThe consolidated financial statements include our accounts and those of our wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.
Foreign Currency Translation	The functional currencies of certain of our foreign subsidiaries are the local currencies and, accordingly, all assets and liabilities of these foreign operations are translated to U.S. Dollars at current period-end exchange rates, and revenues and expenses are translated to U.S. Dollars using average exchange rates in effect during the period. The gains and losses from the foreign currency translation of these subsidiaries' financial statements are included as a separate component of stockholders' equity on our Consolidated Balance Sheets under Accumulated other comprehensive loss. Certain other of our foreign subsidiaries use the U.S. Dollar as their functional currency. Accordingly, monetary assets and liabilities in non-functional currencies of these subsidiaries are remeasured using exchange rates in effect at the end of the period. Revenues and costs in local currency are remeasured using average exchange rates for the period, except for costs related to those balance sheet items that are remeasured using historical exchange rates. The resulting remeasurement gains and losses are included in the Consolidated Statements of Income as a component of Other income, net as incurred.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Estimates may change as new information is obtained. We believe that the estimates, assumptions and judgments involved in revenue recognition, fair value of marketable securities, fair value of derivative financial instruments used to hedge both foreign currency and interest rate exposures, allowance for credit losses, reserves for product warranty, valuation of obsolete and slow moving inventory, assets acquired and liabilities assumed in business combinations, legal contingencies, valuation of goodwill, the assessment of recoverability of long-lived assets, valuation and recognition of stock-based compensation, loss contingencies, provision for income taxes and valuation of deferred tax assets have the greatest potential impact on our consolidated financial statements. Actual results could differ from those estimates.
Business Acquisitions	Business Acquisitions Our consolidated financial statements include the operations of acquired businesses after the completion of their respective acquisitions. We account for acquired businesses using the acquisition method of accounting, which requires, among other things, that assets acquired and liabilities assumed be recognized at their estimated fair values as of the acquisition date, and that the fair value of acquired intangibles be recorded on the balance sheet. Transaction costs are expensed as incurred. Any excess of the purchase price over the assigned fair values of the net assets acquired is recorded as goodwill.
Cash and Cash Equivalents	Cash and Cash Equivalents and Marketable SecuritiesCash and cash equivalents consist of deposits and financial instruments which are readily convertible into cash and have original maturities of 90 days or less at the time of acquisition.
Marketable Securities	Marketable securities consist primarily of highly liquid investments with maturities of greater than 90 days when purchased. We classify our available-for-sale marketable securities as current assets because they represent investments of cash available for current operations. As a result, the Company recorded all its marketable securities in short-term investments regardless of the contractual maturity date of the securities. Furthermore, we report them at fair value with the related unrealized gains and losses included in Accumulated other comprehensive loss in our Consolidated Balance Sheets. Any unrealized losses which are considered to be other-than-temporary are recorded in Other income, net, in the Consolidated Statements of Income. Realized gains and losses on the sale of marketable securities are determined using the specific-identification method and recorded in Other income, net, in the Consolidated Statements of Income. All of our available-for-sale investments are subject to a periodic impairment review. If an available-for-sale debt security’s fair value is less than its amortized cost basis, then we evaluate whether the decline is the result of a credit loss, in which case an impairment is recorded through an allowance for credit losses. Unrealized gains and losses not attributable to credit losses are included, net of tax, in Accumulated other comprehensive loss in our Consolidated Balance Sheets.
Foreign Exchange Management	Foreign Exchange Management We transact business in various foreign currencies. We enter into forward foreign exchange contracts in an effort to mitigate the risks associated with currency fluctuations on certain foreign currency balance sheet exposures and certain operational costs denominated in local currency impacting our statement of income. For accounting purposes, certain of our foreign currency forward contracts are not designated as hedging instruments and, accordingly, we record the fair value of these contracts as of the end of our reporting period in our Consolidated Balance Sheets with changes in fair value recorded within Other income, net in our Consolidated Statements of Income for both realized and unrealized gains and losses. Certain of our foreign currency forward contracts are designated as cash flow hedges, and, accordingly, we record the fair value of these contracts as of the end of our reporting period in our Consolidated Balance Sheets with changes in fair value recorded as a component of Accumulated other comprehensive loss and reclassified into earnings in the same period in which the hedged transaction affects earnings, and in the same line item on the Consolidated Statements of Income as the impact of the hedge transaction. We do not use derivative financial instruments for trading or speculative purposes.
Accounts Receivable and Allowance for Credit Losses	Accounts Receivable and Allowance for Credit Losses The majority of our accounts receivable are derived from sales to large multinational semiconductor manufacturers throughout the world, are recorded at their invoiced amount, and do not bear interest. In order to monitor potential credit losses, we perform ongoing credit evaluations of our customers' financial condition. An allowance for credit losses is maintained based upon our assessment of the expected collectability of all accounts receivable. The allowance for credit losses is reviewed and assessed for adequacy on a quarterly basis. We take into consideration (1) any circumstances of which we are aware of a customer's inability to meet its financial obligations and (2) our judgments as to prevailing economic conditions in the industry and their impact on our customers. If circumstances change, and the financial condition of our customers is adversely affected and they are unable to meet their financial obligations, we may need to take additional allowances, which would result in an increase in our operating expense.
Inventories	Inventories We state our inventories at the lower of cost (principally standard cost which approximates actual cost on a first in, first out basis) or net realizable value. We regularly assess the value of our inventory and will periodically write down its value for estimated excess inventory and product obsolescence based upon an analysis of existing inventory quantities compared to estimated future consumption. Future consumption is estimated based upon assumptions about how past consumption, recent purchases, backlog and other factors may indicate future consumption. On a quarterly basis, we review existing inventory quantities in comparison to our past consumption, recent purchases, backlog and other factors to determine what inventory quantities, if any, may not be sellable. Based on this analysis, we record an adjustment to the cost basis of inventory when evidence exists that the net realizable value of inventory is lower than its cost, which occurs when we have excess and/or obsolete inventory. Once the value is adjusted, the original cost of our inventory, less the related inventory write-down, represents the new cost basis. Reversal of these write downs is recognized only when the related inventory has been scrapped or sold. Shipping and handling costs are classified as a component of Cost of revenues in the Consolidated Statements of Income. We design, manufacture and sell a custom product into a market that has been subject to cyclicality and significant demand fluctuations. Many of our products are complex, custom to a specific chip design and have to be delivered on short lead-times. Probe cards are manufactured in low volumes, but, for certain materials, the purchases are often subject to minimum order quantities in excess of the actual underlying probe card demand. It is not uncommon for us to acquire production materials and commence production activities based on estimated production yields and forecasted demand prior to, or in excess of, actual demand for our probe cards. These factors result in normal recurring inventory valuation charges to Cost of revenues.
Restricted Cash	Restricted CashRestricted cash is comprised primarily of funds held by our foreign subsidiaries for employee obligations, office leases, customer deposits, temporary customs import permits, and environmental remediation.
Property, Plant, and Equipment	Property, Plant, and Equipment Property, plant and equipment is stated at cost less accumulated depreciation and amortization. Depreciation is recorded on a straight-line method. Machinery and equipment, computer equipment and software, and furniture and fixtures are depreciated over 3 to 5 years. Leasehold improvements are amortized over 7 years. Building and building improvements are depreciated over 30 years. Construction-in-progress assets are not depreciated until the assets are placed in service. Upon sale or retirement of assets, the cost and related accumulated depreciation or amortization are removed from the Consolidated Balance Sheets and the resulting gain or loss, if any, is reflected in Operating income in our Consolidated Statements of Income.
Leases	Leases The Company determines if an arrangement is a lease at its inception. Right-of-use (“ROU”) assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. We use our estimated incremental borrowing rate in determining the present value of lease payments considering the term of the lease, which is derived from information available at the lease commencement date. The lease term includes renewal options when it is reasonably certain that the option will be exercised and excludes termination options. To the extent that the Company’s agreements have variable lease payments, the Company includes variable lease payments that depend on an index or a rate and excludes those that depend on facts or circumstances occurring after the commencement date, other than the passage of time. Lease expense for these leases is recognized on a straight-line basis over the lease term. We have elected not to recognize ROU assets and lease liabilities that arise from short-term leases for any class of underlying asset. Operating leases are included in Operating lease, right-of-use-assets, Operating lease liabilities, and Long-term operating lease liabilities in our Consolidated Balance Sheets.
Goodwill	Goodwill Goodwill represents the excess of the purchase price over the fair value of identifiable assets acquired and liabilities assumed. Goodwill is not amortized, rather assessed, at least annually, for impairment at a reporting unit level. Impairment of goodwill exists when the carrying amount of a reporting unit exceeds its fair value. A goodwill impairment loss is recognized for the amount that the carrying amount of the reporting unit, including goodwill, exceeds its fair value, limited to the total amount of goodwill allocated to that reporting unit. If the fair value of a reporting unit exceeds the carrying amount, goodwill of the reporting unit is not considered impaired. We evaluate impairment by first assessing qualitative factors to determine whether it is necessary to perform a quantitative impairment test. If we determine, as a result of the qualitative assessment, that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, then the quantitative impairment test is required. Otherwise, no further testing is required. We perform our annual goodwill impairment test in the fourth quarter of each year by assessing qualitative factors, including, but not limited to, an assessment of our market capitalization, which was significantly higher than our book value. Based on these tests, we determined that the quantitative impairment test was not required and no impairment charges were recorded in fiscal 2022, 2021 or 2020. The evaluation of goodwill for impairment requires the exercise of judgment. In the event of future changes in business conditions, we will be required to reassess and update our forecasts and estimates used in future impairment analysis. If the results of these analysis are lower than current estimates, a material impairment charge may result at that time.
Intangible Assets	Intangible Assets Intangible assets consist of acquisition related intangible assets and intellectual property. The intangible assets are being amortized over periods of 1 to 10 years, which reflect the pattern in which economic benefits of the assets are expected to be realized. We perform a review of intangible assets when facts and circumstances indicate that the useful life is shorter than originally estimated or that the carrying amount of assets may not be recoverable. Such facts and circumstances include significant adverse changes in the business climate or legal factors; current period cash flow or operating losses combined with a history of losses or a forecast of continuing losses associated with the use of the intangible assets; and current expectation that the intangible assets will more likely than not be sold or disposed of before the end of their estimated useful lives. We assess the recoverability of identified intangible assets by comparing the projected undiscounted net cash flows associated with the related asset or group of assets over their remaining lives against their respective carrying amounts. Impairments, if any, are based on the excess of the carrying amount over the fair value of those assets.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets We test long-lived assets or asset groups, such as property, plant and equipment and intangible assets, for recoverability when events or changes in circumstances indicate that their carrying amounts may not be recoverable. Circumstances which could trigger a review include, but are not limited to: significant decreases in the market price of the asset; significant adverse changes in the business climate or legal factors; accumulation of costs significantly in excess of the amount originally expected for the acquisition or construction of the asset; current period cash flow or operating losses combined with a history of losses or a forecast of continuing losses associated with the use of the asset; and current expectation that the asset will more likely than not be sold or disposed of before the end of its estimated useful life. Recoverability is assessed based on the carrying amounts of the asset or asset group and the sum of the undiscounted cash flows expected to result from the use and the eventual disposal of the asset. An impairment loss is recognized when the carrying amount is not recoverable and exceeds fair value.
Concentration of Credit Risk and Other Risk and Uncertainties	Concentration of Credit Risk and Other Risks and UncertaintiesFinancial instruments that potentially subject us to concentrations of credit risk consist primarily of cash equivalents, marketable securities and accounts receivable. Our cash equivalents and marketable securities are held in safekeeping by large, credit-worthy financial institutions. We invest our excess cash primarily in U.S. banks, government and agency bonds, money market funds and corporate obligations. We have established guidelines relative to credit ratings, diversification and maturities that seek to maintain safety and liquidity. Deposits in these banks may exceed the amounts of insurance provided on such deposits. To date, we have not experienced any losses on our deposits of cash and cash equivalents. We market and sell our products to a relatively narrow base of customers and generally do not require collateral.
Revenue Recognition	Revenue Recognition Revenue is recognized upon transferring control of products and services, and the amounts recognized reflect the consideration we expect to be entitled to receive in exchange for these products and services. Revenue is recognized net of any taxes collected from customers, which are subsequently remitted to governmental authorities. An arrangement may include some or all of the following products and services: probe cards, systems, accessories, engineering services, installation services, service contracts and extended warranty contracts. We sell our products and services direct to customers and to partners in two distribution channels: global direct sales force and through a combination of manufacturers’ representatives and distributors. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. In contracts with multiple performance obligations, we identify each performance obligation and evaluate whether the performance obligation is distinct within the context of the contract at contract inception. Performance obligations that are not distinct at contract inception are combined and accounted for as one unit of account. Generally, the performance obligations in a contract are considered distinct within the context of the contract and are accounted for as separate units of account. Our products may be customized to our customers’ specifications; however, control of our product is typically transferred to the customer at the point in time the product is either shipped or delivered, depending on the terms of the arrangement, as the criteria for over time recognition is not met. In limited circumstances, substantive acceptance by the customer exists which results in the deferral of revenue until acceptance is formally received from the customer. Judgment may be required in determining if the acceptance clause is substantive. In certain instances control of products is transferred to the customer over time based on performance and in those instances we utilize an appropriate input or output measure to determine to what extent control has transferred to the customer. Judgment may be required in determining an appropriate measure of performance. Installation services are routinely provided to customers purchasing our systems. Installation services are a distinct performance obligation apart from the systems and are recognized in the period they are performed. Service contracts, which include repair and maintenance service contracts, and extended warranty contracts are also distinct performance obligations and are recognized over the contractual service period, which ranges from one to three years. For these service contracts recognized over time, we use the input measure of days elapsed to measure progress. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. In determining the transaction price, we evaluate whether the price is subject to refund or adjustment to determine the net consideration to which we expect to be entitled. We generally do not grant return privileges, except for defective products during the warranty period. Sales incentives and other programs that we may make available to our customers are considered to be a form of variable consideration, which is estimated in determining the contract’s transaction price to be allocated to the performance obligations. For contracts with multiple performance obligations, we allocate the contract’s transaction price to each performance obligation based on its relative stand-alone selling price. The stand-alone selling prices are determined based on observable prices, which are the prices at which we separately sell these products. For items which do not have observable prices, we use our best estimate of the stand-alone selling prices. Transaction price allocated to the remaining performance obligations: On December 31, 2022, we had $7.5 million of remaining performance obligations, which were comprised of deferred service contracts, extended warranty contracts, and contracts with over time revenue recognition that are not yet delivered. We expect to recognize approximately 85.7% of our remaining performance obligations as revenue in fiscal 2023, approximately 9.6% in fiscal 2024, and approximately 4.7% in fiscal 2025 and thereafter. The foregoing excludes the value of remaining performance obligations that have original durations of one year or less, and also excludes information about variable consideration allocated entirely to a wholly unsatisfied performance obligation. Contract balances: The timing of revenue recognition may differ from the timing of invoicing to customers. Accounts receivable is recorded at the invoiced amount, net of an allowance for credit losses. A receivable is recognized in the period we deliver goods or provide services or when our right to consideration is unconditional. A contract asset is recorded when we have performed under the contract but our right to consideration is conditional on something other than the passage of time. Contract assets as of December 31, 2022 and December 25, 2021 were $1.9 million and $0.9 million, respectively, and are reported on the Consolidated Balance Sheets as a component of Prepaid expenses and other current assets. Contract liabilities include payments received and payments due in advance of performance under a contract and are satisfied as the associated revenue is recognized. Contract liabilities are reported on the Consolidated Balance Sheets on a contract-by-contract basis at the end of each reporting period as a component of Deferred revenue and Other liabilities. Contract liabilities totaled $30.9 million and $24.2 million at December 31, 2022 and December 25, 2021, respectively. During fiscal 2022, we recognized $20.1 million of revenue that was included in contract liabilities as of December 25, 2021. Costs to obtain a contract: We generally expense sales commissions when incurred as a component of Selling, general and administrative expense as the amortization period is typically less than one year. Revenue by Category: Refer to Note 16, Segments and Geographic Information, for further details.
Warranty Obligations	Warranty Obligations We offer warranties on certain products and record a liability for the estimated future costs associated with warranty claims at the time revenue is recognized. The warranty liability is based upon historical experience and our estimate of the level of future costs. While we engage in product quality programs and processes, our warranty obligation is affected by product failure rates, material usage and service delivery costs incurred in correcting a product failure. We continuously monitor product returns for warranty and maintain a reserve for the related expenses based upon our historical experience and any specifically identified field failures. As we sell new products to our customers, we must exercise considerable judgment in estimating the expected failure rates. This estimating process is based on historical experience of similar products, as well as various other assumptions that we believe to be reasonable under the circumstances. We provide for the estimated cost of product warranties at the time revenue is recognized. Warranty costs are reflected in the Consolidated Statement of Income as a Cost of revenues.
Research and Development	Research and Development Research and development expenses include expenses related to product development, engineering and material costs. All research and development costs are expensed as incurred.
Income Taxes	Income Taxes We utilize the asset and liability method of accounting for income taxes, under which deferred taxes are determined based on the temporary differences between the financial statement and tax basis of assets and liabilities using tax rates expected to be in effect during the years in which the basis differences reverse and for operating losses and tax credit carryforwards. We estimate our provision for income taxes and amounts ultimately payable or recoverable in numerous tax jurisdictions around the world. Estimates involve interpretations of regulations and are inherently complex. Resolution of income tax treatments in individual jurisdictions may not be known for many years after completion of any fiscal year. We are required to evaluate the realizability of our deferred tax assets on an ongoing basis to determine whether there is a need for a valuation allowance with respect to such deferred tax assets. A valuation allowance is recorded when it is more likely than not that some or all of the deferred tax assets will not be realized. In evaluating the ability to recover deferred tax assets, we consider all available positive and negative evidence giving greater weight to our recent cumulative income, our historical ability to utilize net operating losses in recent years, and our forecast of future taxable income, including the reversal of temporary differences and the implementation of feasible and prudent tax planning strategies. We recognize and measure uncertain tax positions taken or expected to be taken in a tax return if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized are then measured based on the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement. We report a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. We adjust these reserves in light of changing facts and circumstances, such as the closing of a tax audit or the refinement of an estimate. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will impact the provision for income taxes in the period in which such determination is made. The provision for income taxes includes the impact of reserve provisions and changes to reserves, as well as the related net interest. We recognize interest and penalties related to unrecognized tax benefits within the income tax provision. Accrued interest and penalties are included within the related tax liability in the Consolidated Balance Sheets. We file annual income tax returns in multiple taxing jurisdictions around the world. A number of years may elapse before an uncertain tax position is audited and finally resolved. While it is often difficult to predict the final outcome or the timing of resolution of any particular uncertain tax position, we believe that our related liability reflects the most likely outcome. We adjust the liability, as well as the related interest, in light of changing facts and circumstances. Settlement of any particular position could require the use of cash.
Stock-Based Compensation	Stock-Based Compensation We recognize compensation expense for all stock-based awards based on the grant-date estimated fair values. The value of the portion of the award that is ultimately expected to vest is recognized as expense ratably over the requisite service periods in our Consolidated Statements of Income. The fair value of restricted stock units (“RSUs”) is measured based on the closing market price of our common stock on the date of grant. The fair value of Performance RSUs (“PRSU”) is based on certain market performance criteria and is measured using a Monte Carlo simulation pricing model. See Note 12, Stockholders' Equity, and Note 13, Stock-Based Compensation, for additional information.
Net Income Per Share	Net Income Per ShareBasic net income per share is computed by dividing net income by the weighted-average number of common shares outstanding for the period. Diluted net income per share is computed giving effect to all potentially dilutive common stock and common stock equivalents, including stock options, RSUs and common stock subject to repurchase.
Fair Value Measurement	Whenever possible, the fair values of our financial assets and liabilities are determined using quoted market prices of identical securities or quoted market prices of similar securities from active markets. The three levels of inputs that may be used to measure fair value are as follows: •Level 1 valuations are obtained from real-time quotes for transactions in active exchange markets involving identical securities; •Level 2 valuations utilize significant observable inputs, such as quoted prices for similar assets or liabilities, quoted prices near the reporting date in markets that are less active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and •Level 3 valuations utilize unobservable inputs to the valuation methodology and include our own data about assumptions market participants would use in pricing the asset or liability based on the best information available under the circumstances. We did not have any transfers of assets or liabilities measured at fair value on a recurring basis to or from Level 1, Level 2 or Level 3 during fiscal 2022, 2021 or 2020. The carrying values of Cash, Accounts receivable, net, Restricted cash, Prepaid expenses and other current assets, Accounts payable, and Accrued liabilities approximate fair value due to their short maturities. No changes were made to our valuation techniques during fiscal 2022. Cash Equivalents The fair value of our cash equivalents is determined based on quoted market prices for similar or identical securities. Marketable Securities We classify our marketable securities as available-for-sale and value them utilizing a market approach. Our investments are priced by pricing vendors who provide observable inputs for their pricing without applying significant judgment. Broker pricing is used mainly when a quoted price is not available, the investment is not priced by our pricing vendors or when a broker price is more reflective of fair value. Our broker-priced investments are categorized as Level 2 investments because fair value is based on similar assets without applying significant judgments. In addition, all of our investments have a sufficient level of trading volume to demonstrate that the fair value is appropriate.
New Accounting Pronouncements	ASU 2021-08 In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers. The new guidance requires contract assets and contract liabilities acquired in a business combination to be recognized and measured by the acquirer on the acquisition date in accordance with Accounting Standards Codification 606, “Revenue from Contracts with Customers,” as if it had originated the contracts. The Company elected to early adopt on a prospective basis during the second quarter of fiscal 2022. The adoption did not have a material effect on the Company's Consolidated Financial Statements.

CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Statement of Financial Position [Abstract]
Current unamortized debt issuance costs	$ 5	$ 5
Noncurrent unamortized debt issuance costs	$ 60	$ 65
Preferred stock par value (in USD per share)	$ 0.001	$ 0.001
Preferred stock authorized (in shares)	10,000,000	10,000,000
Preferred stock issued (in shares)	0	0
Preferred stock outstanding (in shares)	0	0
Common stock, par value (in USD per share)	$ 0.001	$ 0.001
Common stock authorized (in shares)	250,000,000	250,000,000
Common stock issued (in shares)	76,914,590	78,240,506
Common stock outstanding (in shares)	76,914,590	78,240,506

Restructuring Charges - Schedule of Restructuring Accrual Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, beginning balance	$ 2,478	$ 0
Restructuring charges	15,586	5,621
Cash payments	(9,991)
Adjustment to restructuring charges	(147)	(1,497)
Non-cash settlement	(6,677)	(1,646)
Restructuring reserve, ending balance	1,249	2,478
Operating Expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	15,439	4,124
Cost of revenues
Restructuring Cost and Reserve [Line Items]
Restructuring charges	11,775	3,205
Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,498	869
Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2,166	50
Employee Severance and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, beginning balance	1,028	0
Restructuring charges	7,269	1,175
Cash payments	(7,048)
Adjustment to restructuring charges	0	(147)
Non-cash settlement	0	0
Restructuring reserve, ending balance	1,249	1,028
Contract Termination & Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, beginning balance	1,450	0
Restructuring charges	502	2,800
Cash payments	(1,719)
Adjustment to restructuring charges	(147)	(1,350)
Non-cash settlement	(86)	0
Restructuring reserve, ending balance	0	1,450
Inventory Impairments & Other Inventory Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, beginning balance	0	0
Restructuring charges	7,629	1,376
Cash payments	(1,112)
Adjustment to restructuring charges	0	0
Non-cash settlement	(6,517)	(1,376)
Restructuring reserve, ending balance	0	0
Property and Equipment Impairments & Other Asset Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, beginning balance	0	0
Restructuring charges	186	270
Cash payments	(112)
Adjustment to restructuring charges	0	0
Non-cash settlement	(74)	(270)
Restructuring reserve, ending balance	$ 0	$ 0

Summary of Significant Accounting Policies - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Accounting Policies [Abstract]
Unrealized losses on available-for-sale marketable securities and other investments	$ (2,749)	$ (724)
Translation adjustments	(5,675)	(811)
Unrealized gains on derivative instruments	2,846	86
Accumulated other comprehensive loss	$ (5,578)	$ (1,449)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References + Details

Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of year	$ 195	$ 248	$ 222
Charges (reversals) to costs and expenses	(27)	(53)	26
Balance at end of year	$ 168	$ 195	$ 248

Balance Sheet Components - Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Balance Sheet Components [Abstract]
Raw materials	$ 55,726	$ 57,673
Work-in-progress	46,067	35,935
Finished goods	21,364	17,940
Inventory, net	$ 123,157	$ 111,548