0001039399-17-000026 | 10-Q | XBRL Viewer

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Apr. 01, 2017	May 09, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	FORMFACTOR INC.
Entity Central Index Key	0001039399
Current Fiscal Year End Date	--12-30
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Apr. 01, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		72,121,454

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Income Statement [Abstract]
Revenues	$ 128,829	$ 53,611
Cost of revenues	81,258	43,819
Gross profit	47,571	9,792
Operating expenses:
Research and development	17,414	10,849
Selling, general and administrative	22,829	12,516
Restructuring charges	269	0
Total operating expenses	40,512	23,365
Operating income (loss)	7,059	(13,573)
Interest income, net	67	117
Other income (expense), net	(1,574)	(314)
Income (loss) before income taxes	5,552	(13,770)
Provision for income taxes	367	30
Net income (loss)	$ 5,185	$ (13,800)
Net income (loss) per share:
Basic (In dollars per share)	$ 0.07	$ (0.24)
Diluted (In dollars per share)	$ 0.07	$ (0.24)
Weighted-average number of shares used in per share calculations:
Basic (In shares)	71,423	58,431
Diluted (In shares)	72,922	58,431

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 5,185	$ (13,800)
Other comprehensive income, net of tax:
Foreign currency translation adjustments	1,447	603
Unrealized gains on available-for-sale marketable securities	0	38
Unrealized gains on derivative instruments	157	0
Other comprehensive income, net of tax	1,604	641
Comprehensive income (loss)	$ 6,789	$ (13,159)

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 114,437	$ 101,408
Marketable securities	7,497	7,497
Accounts receivable, net	79,439	70,225
Inventories, net	60,371	59,806
Restricted cash	4	106
Refundable income taxes	1,105	1,391
Prepaid expenses and other current assets	11,348	14,276
Total current assets	274,201	254,709
Restricted cash	1,116	1,082
Property, plant and equipment, net	45,153	42,663
Goodwill	188,185	188,010
Intangibles, net	118,444	126,608
Deferred tax assets	3,322	3,310
Other assets	2,246	2,600
Total assets	632,667	618,982
Current liabilities:
Accounts payable	43,316	34,075
Accrued liabilities	26,292	30,184
Current portion of term loan	14,601	12,701
Income taxes payable	50	442
Deferred revenue	6,590	5,305
Total current liabilities	90,849	82,707
Long-term income taxes payable	1,290	1,315
Term loan, less current portion	116,872	125,475
Deferred tax liabilities	3,770	3,703
Deferred rent and other liabilities	4,536	4,726
Total liabilities	217,317	217,926
Commitments and contingencies (Note 12)
Stockholders’ equity:
Preferred stock, $0.001 par value: 10,000,000 shares authorized; no shares issued and outstanding at April 1, 2017 and December 31, 2016, respectively	0	0
Common stock, $0.001 par value: 250,000,000 shares authorized; 71,672,152 and 70,907,847 shares issued and outstanding at April 1, 2017 and December 31, 2016, respectively	72	71
Additional paid-in capital	840,714	833,341
Accumulated other comprehensive loss	(2,135)	(3,740)
Accumulated deficit	(423,301)	(428,616)
Total stockholders’ equity	415,350	401,056
Total liabilities and stockholders’ equity	$ 632,667	$ 618,982

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Apr. 01, 2017	Dec. 31, 2016
Stockholders' Equity:
Preferred stock, par value (In dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (In shares)	10,000,000	10,000,000
Preferred stock, shares issued (In shares)	0	0
Preferred stock, shares outstanding (In shares)	0	0
Common stock, par value (In dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (In shares)	250,000,000	250,000,000
Common stock, shares issued (In shares)	71,672,152	70,907,847
Common stock, shares outstanding (In shares)	71,672,152	70,907,847

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Cash flows from operating activities:
Net income (loss)	$ 5,185	$ (13,800)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation	3,162	2,468
Amortization	8,349	2,771
Accretion of discount on investments	0	(16)
Stock-based compensation expense	3,302	2,734
Amortization of debt issuance costs	171	0
Deferred income tax provision	81	0
Recovery of doubtful accounts receivable	0	(34)
Provision for excess and obsolete inventories	2,797	1,989
Acquired inventory step-up amortization	190	0
Loss on sale of long-lived assets	22	0
Gain on derivative instruments	(65)	0
Foreign currency transaction gains	(729)	(1,393)
Changes in assets and liabilities:
Accounts receivable	(8,888)	1,260
Inventories	(3,345)	(5,750)
Prepaid expenses and other current assets	3,068	2,108
Refundable income taxes	286	0
Other assets	615	(286)
Accounts payable	7,220	8,824
Accrued liabilities	(4,780)	(3,597)
Income tax payable	(419)	(2)
Deferred rent and other liabilities	71	178
Deferred revenues	1,510	(486)
Net cash provided by (used in) operating activities	17,803	(3,032)
Cash flows from investing activities:
Acquisition of property, plant and equipment	(3,465)	(1,111)
Proceeds from sale of subsidiary	14	9
Purchases of marketable securities	0	(6,591)
Proceeds from maturities of marketable securities	0	12,700
Change in restricted cash	121	0
Net cash (used in) provided by investing activities	(3,330)	5,007
Cash flows from financing activities:
Proceeds from issuances of common stock	7,437	1,961
Purchase and retirement of common stock	(2,733)	0
Tax withholdings related to net share settlements of equity awards	(480)	0
Payments on term loan debt	(6,875)	0
Net cash (used in) provided by financing activities	(2,651)	1,961
Effect of exchange rate changes on cash and cash equivalents	1,207	1,713
Net increase in cash and cash equivalents	13,029	5,649
Cash and cash equivalents, beginning of period	101,408	146,264
Cash and cash equivalents, end of period	114,437	151,913
Non-cash investing and financing activities:
Changes in accounts payable and accrued liabilities related to property, plant and equipment purchases	2,035	1,166
Supplemental disclosure of cash flow information:
Income and property taxes paid, net	$ 407	$ 22

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Apr. 01, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Basis of Presentation and Summary of Significant Accounting Policies Basis of presentation. The condensed consolidated financial information included herein has been prepared by FormFactor, Inc. without audit, in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). However, such information reflects all adjustments, consisting only of normal recurring adjustments, which are, in the opinion of management, necessary for a fair presentation of the financial position, results of operations and cash flows for the interim periods. The financial information as of December 31, 2016 is derived from our 2016 Annual Report on Form 10-K. The condensed consolidated financial statements included herein should be read in conjunction with the consolidated financial statements and the notes thereto included in our 2016 Annual Report on Form 10-K. The results of operations for the interim periods presented are not necessarily indicative of the results to be expected for the full year. Fiscal year. We operate on a 52/53 week fiscal year, whereby the fiscal year ends on the last Saturday of December. Fiscal 2017 and 2016 contain 52 weeks and 53 weeks, respectively and the three months ended April 1, 2017 and March 26, 2016 each contained 13 weeks. Fiscal 2017 will end on December 30, 2017. Business Acquisition. On June 24, 2016, we completed the acquisition of Cascade Microtech Inc. ("Cascade Microtech"), headquartered in Beaverton, Oregon. Our condensed consolidated financial statements as of April 1, 2017 included the condensed consolidated balance sheet of Cascade Microtech as of April 1, 2017 and the condensed consolidated statement of operations of Cascade Microtech for the three months ended April 1, 2017 whereas our condensed consolidated financial statements as of and for the three months ended March 26, 2016 excluded the financial position and operations of Cascade Microtech. See Note 3 to the Condensed Consolidated Financial Statements - Acquisition, for further details. Critical Accounting Policies. Our critical accounting policies have not changed during the three months ended April 1, 2017 from those disclosed in our Annual Report on Form 10-K for the year ended December 31, 2016. New Accounting Pronouncements. In March 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-09, "Improvements to Employee Share-Based Payment Accounting", which amends Accounting Standards Codification ("ASC") Topic 718, "Compensation - Stock Compensation". The ASU includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements including: 1) excess tax benefits and tax deficiencies relating to share based payment awards will be recognized as income tax benefit or expense in the reporting period in which they occur (previously such amounts were recognized in additional paid-in capital); 2) excess tax benefits will be classified as an operating activity in the statement of cash flows; and 3) the option to elect to estimate forfeitures or account for them when they occur. We adopted ASU 2016-09 as of January 1, 2017, which is the first day of our fiscal 2017 and made an accounting policy election to account for forfeitures as incurred resulting in a decrease of $0.1 million in our accumulated deficit on January 1, 2017. The adjustment was reflected in our condensed consolidated balance sheet as of this date. Additionally, we determined that there was no cumulative effect on retained earnings or other components of equity or net assets as of the beginning of the period of adoption of this guidance as the impact of recording cumulative excess tax benefits in income taxes in our condensed consolidated statement of earnings was fully offset by a valuation allowance as of the date of adoption. Finally, we will follow the prospective transition method for the recognition of windfalls and shortfalls associated with excess tax benefits and tax deficiencies relating to share based payment awards.

Concentration of Credit and Other Risks

3 Months Ended

Apr. 01, 2017

Risks and Uncertainties [Abstract]

Concentration of Credit and Other Risks

We market and sell our products to a narrow base of customers and generally do not require collateral. Each of the following customers accounted for more than 10% of our revenues for the periods indicated:



	Three Months Ended
	April 1, 2017		March 26, 2016
Intel	26.7	%	34.3	%
Samsung	10.3		10.4
Total revenues attributable to customers greater than 10%	37.0	%	44.7	%

At April 1, 2017, one customer accounted for approximately 22% of gross accounts receivable. At December 31, 2016, one customer accounted for approximately 21% of gross accounts receivable. No other customers accounted for more than 10% of gross accounts receivable at either of these fiscal period ends.

Acquisition

3 Months Ended

Apr. 01, 2017

Business Combinations [Abstract]

Acquisition

On June 24, 2016, we acquired Cascade Microtech which was accounted for using the acquisition method of accounting in accordance with the FASB ASC Topic No. 805, Business Combinations. The acquired assets and liabilities of Cascade Microtech 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.

The table below summarizes the assets acquired and liabilities assumed as of April 1, 2017 and December 31, 2016 (in thousands):



	Amount
Cash and cash equivalents	$	40,681
Accounts receivable	27,112
Inventory	38,315
Prepaid expenses and other current assets	6,249
Property, plant and equipment	19,875
Other long-term assets	818
Deferred revenue	(1,829		)
Accounts payable and accrued liabilities	(23,370		)
Deferred tax liabilities	(48,993		)
Other long-term liabilities	(960		)
Total tangible assets acquired and liabilities assumed	57,898
Intangible assets	149,753
Goodwill	158,141
Total acquisition price	$	365,792

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. Asset categories acquired included working capital, long-term assets and liabilities and identifiable intangible assets, including in-process research and development ("IPR&D"). The allocation of the acquisition price has been prepared on a preliminary basis and changes to that allocation may occur as additional information becomes available.

The fair values assigned to assets acquired and liabilities assumed are based on management’s best estimates and assumptions as of the reporting date and are considered preliminary pending finalization of valuation analyses pertaining to intangible assets acquired, liabilities assumed and tax liabilities assumed including calculation of deferred tax assets and liabilities. Changes to amounts recorded as assets or liabilities may result in corresponding adjustments to goodwill, restructuring and impairment charges, recognized deferred tax assets and liabilities including changes to release of valuation allowance during the measurement period (up to one year from the acquisition date). Any such revisions or changes may be material as we finalize the fair values of the tangible and intangible assets acquired and liabilities assumed.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

+ References

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+ Details

Goodwill and Intangible Assets

3 Months Ended

Apr. 01, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

Goodwill by reportable segments as of April 1, 2017 was as below:



	Probe Cards		Systems		Total
	(in thousands)
Goodwill, gross, as of December 31, 2016	$	172,482	$	15,528	$	188,010
Foreign currency translation	—		175		175
Balance as of April 1, 2017	$	172,482	$	15,703	$	188,185

Goodwill recorded from the acquisition of Cascade Microtech on June 24, 2016 was $158.1 million as of April 1, 2017. See Note 3 to the Condensed Consolidated Financial Statements - Acquisition, for further details. Goodwill recorded from the acquisition of MicroProbe Inc. on October 16, 2012 was $30.7 million as of April 1, 2017. Excluding the impact of foreign currency translation, Goodwill from these acquisitions remained unchanged from the amounts recorded as of December 31, 2016. The Company has not recorded any historical goodwill impairments as of April 1, 2017.

Gross and net intangible assets as of April 1, 2017 and December 31, 2016 were as follows (in thousands, except for weighted average useful life):



	April 1, 2017						December 31, 2016						Weighted Average Useful Life (in years)
Other Intangible Assets	Gross		Accumulated Amortization		Net		Gross		Accumulated Amortization		Net		April 1, 2017
Existing developed technologies	$	142,824	$	61,258	$	81,566	$	142,701	$	56,131	$	86,570	4.1
Trade name	11,934		3,668		8,266		11,921		2,989		8,932		3.8
Customer relationships	39,908		12,200		27,708		39,869		10,854		29,015		5.5
Backlog	15,590		14,686		904		15,581		13,489		2,092		0.0
Total intangible assets	$	210,256	$	91,812	$	118,444	$	210,072	$	83,463	$	126,609

For the three months ended April 1, 2017, amortization expenses of $6.3 million and $2.0 million were included in cost of revenues and selling, general and administrative expenses, respectively. For the three months ended March 26, 2016, amortization expenses of $2.1 million and $0.6 million were included in cost of revenues and selling, general and administrative expenses, respectively.

Based on the carrying values of the intangible assets recorded as of April 1, 2017 and assuming no subsequent additions to or impairment of the underlying assets, the remaining estimated annual amortization expense is expected to be as follows (in thousands):



Fiscal Year	Amount
2017	$	22,366
2018	28,339
2019	25,675
2020	23,605
2021	12,937
and thereafter	5,522
Total	$	118,444

Debt

3 Months Ended

Apr. 01, 2017

Debt Disclosure [Abstract]

Debt

Senior Secured Term Loan Facility

Our debt as of April 1, 2017 consisted of the following (in thousands):



	April 1, 2017
Senior secured term loan	$	132,500
Debt issuance costs	(1,027		)
Total debt less debt issuance costs	$	131,473

As of April 1, 2017, the Company was in compliance with all of the financial covenants under the senior secured term loan facility.

Restructuring Charges

3 Months Ended

Apr. 01, 2017

Restructuring and Related Activities [Abstract]

Restructuring Charges

Restructuring charges are comprised of costs related to employee termination benefits, cost of long-lived assets abandoned or impaired, as well as contract termination costs. Restructuring charges are included in "Restructuring and impairment charges, net" in the Condensed Consolidated Statements of Operations.

During the three months ended April 1, 2017, we recorded approximately $0.3 million of restructuring charges as a result of the consolidation of our operations. The cash payments associated with the restructuring activities are expected to be completed by the end of the third quarter of fiscal 2017. We did not record any restructuring charges during the three months ended March 26, 2016.

The activities in the restructuring accrual for the three months ended April 1, 2017 were as follows (in thousands):



	Employee Severance and Benefits			Contract Termination and Other Costs			Total
Accrual at December 31, 2016	$	330		$	104		$	434
Restructuring charges	248			21			269
Cash payments	(423		)	(35		)	(458		)
Adjustment to restructuring charges	32			—			32
Accrual at April 1, 2017	$	187		$	90		$	277

Fair Value

3 Months Ended

Apr. 01, 2017

Fair Value Disclosures [Abstract]

Fair Value

Assets Measured at Fair Value on a Recurring Basis

We measure and report certain assets and liabilities at fair value on a recurring basis, including money market funds, U.S. Treasury securities, agency securities and derivatives comprised of foreign currency forward contracts and interest-rate swap contracts.

Assets measured at fair value on a recurring basis as of April 1, 2017 were as follows (in thousands):



	Level 1		Level 2		Total
Assets:
Cash equivalents
Money market funds	$	19,388	$	—	$	19,388
Marketable securities
U.S. Treasuries	—		7,497		7,497
Interest rate swap derivative contracts	—		1,009		1,009
Total assets	$	19,388	$	8,506	$	27,894

Assets measured at fair value on a recurring basis as of December 31, 2016 were as follows (in thousands):



	Level 1		Level 2		Total
Assets:
Cash equivalents
Money market funds	$	19,350	$	—	$	19,350
Marketable securities
U.S. Treasuries	—		7,497		7,497
Foreign exchange derivative contracts	—		1,137		1,137
Interest rate swap derivative contracts	—		838		838
Total	$	19,350	$	9,472	$	28,822

The Level 1 assets consist of our money market fund deposits. The Level 2 assets consist of our available-for-sale investment portfolio, which are valued utilizing a market approach, and derivative contracts. Our investments are priced by pricing vendors who provided 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 values in the market in which the investment trades. Our broker-priced investments are labeled as Level 2 investments because fair values of these investments are 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 values used are appropriate for these investments.

Derivative Financial Instruments

Derivative assets and liabilities include foreign currency forward contracts and interest rate swap contracts. We do not use derivative financial instruments for speculative or trading purposes.

Foreign Currency Derivatives

The fair value of foreign currency forward contracts represents the estimated amount required to settle the contracts using current market exchange rates, and is based on the current foreign currency exchange rates and forward points. For accounting purposes, our foreign currency forward contracts are not designated as hedging instruments as defined under ASC 815, Derivatives and Hedging. We record the fair value of these contracts as of the end of our reporting period to our Condensed Consolidated Balance Sheets with changes in fair value recorded within “Other income (expense), net” in our Condensed Consolidated Statements of Income for both realized and unrealized gains and losses.

The location and amount of losses related to non-designated derivative instruments that matured in the three months ended April 1, 2017 and March 26, 2016 in the Condensed Consolidated Statements of Operations are as follows (in thousands):



		Amount of Loss Recognized on Derivatives
		Three Months Ended
Derivatives Not Designated as Hedging Instruments	Location of Loss Recognized on Derivatives	April 1, 2017			March 26, 2016
Foreign exchange forward contracts	Other income (expense), net	$	(886	)	$	(1,562	)

Interest Rate Swaps

For accounting purposes, our interest-rate swap contracts qualify for and are designated as cash flow hedges as defined under ASC 815, Derivatives and Hedging. We recorded approximately $65 thousand of hedge ineffectiveness for the three months ended April 1, 2017. The cash flows associated with the interest rate swaps are reported in net cash provided by operating activities on the Consolidated Statements of Cash Flows.

The estimated fair value of the interest rate swaps as of April 1, 2017 was reported as a derivative asset of approximately $1.0 million, recorded within other assets (current and non-current) on the Company's Condensed Consolidated Balance Sheet and is estimated based on valuation models that use interest rate yield curves as inputs. The inputs used to estimate the fair value of the Company's derivatives are classified as Level 2. We did not have any transfers of assets measured at fair value on a recurring basis to or from Level 1 and Level 2 during the three months ended April 1, 2017 and March 26, 2016.

The impact of the cash flow hedges on the consolidated financial statements is depicted below (in thousands):



The Effect of Derivative Instruments on the Statement of Financial Performance
For the Three Months Ended
	Amount of Gain or (Loss) Recognized in OCI on Derivative (Effective Portion)				Location of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)						Location of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion )	Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion )

Derivatives in ASC 815 Cash Flow Hedging Relationships

	April 1, 2017		March 26, 2016				April 1, 2017			March 26, 2016				April 1, 2017		March 26, 2016
Interest rate contracts	$	120	$	—	Other income (expense), net		$	(37	)	$	—	Other income (expense), net		$	14	$	—
Total	$	120	$	—			$	(37	)	$	—			$	14	$	—

Assets Measured at Fair Value on a Non-Recurring Basis

We measure and report 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. Refer to Note 4 to the Condensed Consolidated Financial Statements-Goodwill and Intangible Assets, for further details. There were no assets measured at fair value on a nonrecurring basis during the three months ended April 1, 2017 and March 26, 2016.

- 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

Inventories

3 Months Ended

Apr. 01, 2017

Inventory Disclosure [Abstract]

Inventories

Inventories consisted of the following (in thousands):



	April 1, 2017		December 31, 2016
Raw materials	$	29,009	$	27,402
Work-in-progress	19,625		20,390
Finished goods	11,737		12,014
	$	60,371	$	59,806

Warranty

3 Months Ended

Apr. 01, 2017

Product Warranties Disclosures [Abstract]

Warranty

A reconciliation of the changes in our warranty liability for the three months ended April 1, 2017 and March 26, 2016, respectively, is as follows (in thousands):



	April 1, 2017			March 26, 2016
Balance at beginning of period	$	2,972		$	1,116
Accruals	1,127			805
Settlements	(1,517		)	(747		)
Balance at the end of period	$	2,582		$	1,174

Stockholders' Equity

3 Months Ended

Apr. 01, 2017

Equity [Abstract]

Stockholders' Equity

Stockholders’ Equity

Common Stock Repurchase Program

In February 2017, our Board of Directors authorized a new program to repurchase up to $25 million of outstanding common stock to offset potential dilution from sales of common stock under our employee stock purchase plan and exercises of stock options. The share repurchase program will expire on February 1, 2020. During the three months ended April 1, 2017, we repurchased and retired 250,000 shares of common stock for approximately $2.7 million.

On April 16, 2015, our Board of Directors authorized a program to repurchase up to $25.0 million of outstanding common stock on the open market which expired on April 15, 2016. During the three months ended March 26, 2016, we did not repurchase any shares under this program.

Repurchased shares are retired upon the settlement of the related trade transactions. Our policy related to repurchases of our common stock is to charge the excess of cost over par value to additional paid-in capital. All repurchases were made in compliance with Rule 10b-18 under the Securities Exchange Act of 1934, as amended.

Restricted Stock Units

Restricted stock unit (RSU) activity under our equity incentive plan during the three months ended April 1, 2017 is set forth below:



	Units		Weighted Average Grant Date Fair Value
Restricted stock units at December 31, 2016	3,108,560		$	8.61
Awards granted	23,622		12.70
Awards vested	(94,608	)	3.51
Awards canceled	(102,721	)	8.70
Restricted stock units at April 1, 2017	2,934,853		$	8.81

The total fair value of RSUs vested during the three months ended April 1, 2017 and March 26, 2016 was $1.2 million and $4.0 million, respectively.

Stock Options

Stock option activity under our equity incentive plan during the three months ended April 1, 2017 is set forth below:



	Options Outstanding		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life in Years	Aggregate Intrinsic Value
Outstanding at December 31, 2016	2,198,031		$	9.13
Options exercised	(560,950	)	8.09
Outstanding at April 1, 2017	1,637,081		$	9.48	2.23	$	4,073,803
Vested and expected to vest at April 1, 2017	1,637,081		$	9.48	2.23	$	4,073,803
Exercisable at April 1, 2017	1,355,147		$	9.84	1.58	$	2,915,206

Stock-Based Compensation

Stock-based compensation was included in our Condensed Consolidated Statements of Operations as follows (in thousands):



	Three Months Ended
	April 1, 2017		March 26, 2016

Cost of revenues	$	854	$	633
Research and development	1,082		796
Selling, general and administrative	1,366		1,305
Total stock-based compensation	$	3,302	$	2,734

Employee Stock Purchase Plan (ESPP)

During the three months ended April 1, 2017 and March 26, 2016, we issued 397,024 and 303,585 ESPP shares, respectively, under our 2012 Employee Stock Purchase Plan.

Unrecognized Compensation Costs

At April 1, 2017, the unrecognized stock-based compensation was as follows (in thousands):



	Unrecognized Expense		Average Expected Recognition Period in Years
Stock options	$	932	1.81
Restricted stock units	17,328		2.04
Employee stock purchase plan	687		0.33
Total unrecognized stock-based compensation expense	$	18,947

- 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

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

Net Income (Loss) per Share

3 Months Ended

Apr. 01, 2017

Earnings Per Share [Abstract]

Net Income (Loss) per Share

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



	Three Months Ended
	April 1, 2017		March 26, 2016
Numerator:
Net income (loss) used in computing basic and diluted net income per share	$	5,185	$	(13,800	)
Denominator:
Weighted-average shares used in computing basic net income (loss) per share	71,423		58,431
Add potentially dilutive securities	1,499		—
Weighted-average shares used in computing basic and diluted net income (loss) per share	72,922		58,431
Securities not included as they would have been antidilutive	126		4,257

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Apr. 01, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Contractual Commitments and purchase obligations Our lease, purchase obligations and contractual obligations have not materially changed as of April 1, 2017 from those disclosed in our Annual Report on Form 10-K for the year ended December 31, 2016. Environmental Matters We did not receive any notices of violations of environmental laws and regulations during the three months ended April 1, 2017, or in our fiscal 2016. 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. We have not recorded any liabilities for these indemnification arrangements on our condensed consolidated balance sheet as of April 1, 2017. Legal Matters From time to time, we may be subject to legal proceedings and claims in the ordinary course of business. As of April 1, 2017 and as of the filing of this Quarterly Report on Form 10-Q, we were not involved in any material legal proceedings other than the proceedings summarized below. 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. On April 8, 2016, an individual plaintiff filed a class action lawsuit against Cascade Microtech, its directors and others, alleging breaches of fiduciary duties in connection with the acquisition of Cascade Microtech by the Company. The lawsuit, captioned Solak v. Cascade Microtech, Inc., et al., was filed in Multnomah County Circuit Court in the State of Oregon. On March 17, 2017, the court entered an Order Granting Final Approval of Class Action Settlement and filed a General Judgment in the case which provided for a payment of plaintiffs’ attorneys’ fees and the dismissal with prejudice of all claims asserted in the action. In August 2013, a former employee filed a class action lawsuit against the Company in the Superior Court of California for the County of Alameda, alleging violations of California’s wage and hour laws and other claims on behalf of himself and all similarly situated current and former employees at the Company’s Livermore facilities from August 21, 2009, onward. On March 14, 2017, the court granted preliminary approval of the parties’ stipulation under which the parties have agreed to settle the lawsuit, subject to court approvals and other conditions. The stipulation provides for payment by the Company of $1.5 million in settlement of the lawsuit. As of April 1, 2017 and December 31, 2016, we have accrued in our Consolidated Financial Statements and Condensed Consolidated Financial Statements, respectively, $1.5 million in respect of the potential payment under the stipulation of settlement.

Operating Segments

3 Months Ended

Apr. 01, 2017

Segment Reporting [Abstract]

Operating Segments

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

The following table summarizes the operating results by reportable segments for the three months ended April 1, 2017 and March 26, 2016 (in thousands, except percentages):



	Three Months Ended
	April 1, 2017												March 26, 2016
	Probe Cards			Systems			Corporate and Other			Total			Probe Cards			Systems			Corporate and Other			Total
Revenues	$	106,496		$	22,333		$	—		$	128,829		$	53,611		$	—		$	—		$	53,611
Gross profit	$	42,820		$	12,090		$	(7,339	)	$	47,571		$	12,509		$	—		$	(2,717	)	$	9,792
Gross margin	40.2		%	54.1		%	—		%	36.9		%	23.3		%	—		%	—		%	18.3		%
Operating income (loss)	$	21,742		$	5,122		$	(19,805	)	$	7,059		$	(2,029	)	$	—		$	(11,544	)	$	(13,573	)

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 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.

- 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

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+ Details

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Apr. 01, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Fiscal Year	Fiscal year. We operate on a 52/53 week fiscal year, whereby the fiscal year ends on the last Saturday of December. Fiscal 2017 and 2016 contain 52 weeks and 53 weeks, respectively and the three months ended April 1, 2017 and March 26, 2016 each contained 13 weeks. Fiscal 2017 will end on December 30, 2017.
New Accounting Pronouncements	New Accounting Pronouncements. In March 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2016-09, "Improvements to Employee Share-Based Payment Accounting", which amends Accounting Standards Codification ("ASC") Topic 718, "Compensation - Stock Compensation". The ASU includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements including: 1) excess tax benefits and tax deficiencies relating to share based payment awards will be recognized as income tax benefit or expense in the reporting period in which they occur (previously such amounts were recognized in additional paid-in capital); 2) excess tax benefits will be classified as an operating activity in the statement of cash flows; and 3) the option to elect to estimate forfeitures or account for them when they occur. We adopted ASU 2016-09 as of January 1, 2017, which is the first day of our fiscal 2017 and made an accounting policy election to account for forfeitures as incurred resulting in a decrease of $0.1 million in our accumulated deficit on January 1, 2017. The adjustment was reflected in our condensed consolidated balance sheet as of this date. Additionally, we determined that there was no cumulative effect on retained earnings or other components of equity or net assets as of the beginning of the period of adoption of this guidance as the impact of recording cumulative excess tax benefits in income taxes in our condensed consolidated statement of earnings was fully offset by a valuation allowance as of the date of adoption. Finally, we will follow the prospective transition method for the recognition of windfalls and shortfalls associated with excess tax benefits and tax deficiencies relating to share based payment awards.
Fair Value Policy	Assets Measured at Fair Value on a Recurring Basis We measure and report certain assets and liabilities at fair value on a recurring basis, including money market funds, U.S. Treasury securities, agency securities and derivatives comprised of foreign currency forward contracts and interest-rate swap contracts. Assets Measured at Fair Value on a Non-Recurring Basis We measure and report 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. Refer to Note 4 to the Condensed Consolidated Financial Statements-Goodwill and Intangible Assets, for further details.

Concentration of Credit and Other Risks (Tables)

3 Months Ended

Apr. 01, 2017

Risks and Uncertainties [Abstract]

Schedule of Customer Percentage of Revenue



	Three Months Ended
	April 1, 2017		March 26, 2016
Intel	26.7	%	34.3	%
Samsung	10.3		10.4
Total revenues attributable to customers greater than 10%	37.0	%	44.7	%

Acquisition (Tables)

3 Months Ended

Apr. 01, 2017

Business Combinations [Abstract]

Schedule of Assets Acquired and Liabilities Assumed

The table below summarizes the assets acquired and liabilities assumed as of April 1, 2017 and December 31, 2016 (in thousands):



	Amount
Cash and cash equivalents	$	40,681
Accounts receivable	27,112
Inventory	38,315
Prepaid expenses and other current assets	6,249
Property, plant and equipment	19,875
Other long-term assets	818
Deferred revenue	(1,829		)
Accounts payable and accrued liabilities	(23,370		)
Deferred tax liabilities	(48,993		)
Other long-term liabilities	(960		)
Total tangible assets acquired and liabilities assumed	57,898
Intangible assets	149,753
Goodwill	158,141
Total acquisition price	$	365,792

Goodwill and Intangible Assets (Tables)

3 Months Ended

Apr. 01, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill by Reportable Segments

Goodwill by reportable segments as of April 1, 2017 was as below:



	Probe Cards		Systems		Total
	(in thousands)
Goodwill, gross, as of December 31, 2016	$	172,482	$	15,528	$	188,010
Foreign currency translation	—		175		175
Balance as of April 1, 2017	$	172,482	$	15,703	$	188,185

Schedule of Finite-Lived Intangible Assets

Gross and net intangible assets as of April 1, 2017 and December 31, 2016 were as follows (in thousands, except for weighted average useful life):



	April 1, 2017						December 31, 2016						Weighted Average Useful Life (in years)
Other Intangible Assets	Gross		Accumulated Amortization		Net		Gross		Accumulated Amortization		Net		April 1, 2017
Existing developed technologies	$	142,824	$	61,258	$	81,566	$	142,701	$	56,131	$	86,570	4.1
Trade name	11,934		3,668		8,266		11,921		2,989		8,932		3.8
Customer relationships	39,908		12,200		27,708		39,869		10,854		29,015		5.5
Backlog	15,590		14,686		904		15,581		13,489		2,092		0.0
Total intangible assets	$	210,256	$	91,812	$	118,444	$	210,072	$	83,463	$	126,609

Schedule of Finite-Lived Intangible Asset Future Amortization Expense



Fiscal Year	Amount
2017	$	22,366
2018	28,339
2019	25,675
2020	23,605
2021	12,937
and thereafter	5,522
Total	$	118,444

Debt (Tables)

3 Months Ended

Apr. 01, 2017

Debt Disclosure [Abstract]

Schedule of Debt

Our debt as of April 1, 2017 consisted of the following (in thousands):



	April 1, 2017
Senior secured term loan	$	132,500
Debt issuance costs	(1,027		)
Total debt less debt issuance costs	$	131,473

Restructuring Charges (Tables)

3 Months Ended

Apr. 01, 2017

Restructuring and Related Activities [Abstract]

Schedule of Restructuring Accrual Activity

The activities in the restructuring accrual for the three months ended April 1, 2017 were as follows (in thousands):



	Employee Severance and Benefits			Contract Termination and Other Costs			Total
Accrual at December 31, 2016	$	330		$	104		$	434
Restructuring charges	248			21			269
Cash payments	(423		)	(35		)	(458		)
Adjustment to restructuring charges	32			—			32
Accrual at April 1, 2017	$	187		$	90		$	277

Fair Value (Tables)

3 Months Ended

Apr. 01, 2017

Fair Value Disclosures [Abstract]

Fair Value Assets Measured on Recurring Basis

Assets measured at fair value on a recurring basis as of April 1, 2017 were as follows (in thousands):



	Level 1		Level 2		Total
Assets:
Cash equivalents
Money market funds	$	19,388	$	—	$	19,388
Marketable securities
U.S. Treasuries	—		7,497		7,497
Interest rate swap derivative contracts	—		1,009		1,009
Total assets	$	19,388	$	8,506	$	27,894

Assets measured at fair value on a recurring basis as of December 31, 2016 were as follows (in thousands):



	Level 1		Level 2		Total
Assets:
Cash equivalents
Money market funds	$	19,350	$	—	$	19,350
Marketable securities
U.S. Treasuries	—		7,497		7,497
Foreign exchange derivative contracts	—		1,137		1,137
Interest rate swap derivative contracts	—		838		838
Total	$	19,350	$	9,472	$	28,822

Schedule of Losses Related to Non-designated Derivative Instruments



		Amount of Loss Recognized on Derivatives
		Three Months Ended
Derivatives Not Designated as Hedging Instruments	Location of Loss Recognized on Derivatives	April 1, 2017			March 26, 2016
Foreign exchange forward contracts	Other income (expense), net	$	(886	)	$	(1,562	)

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

The impact of the cash flow hedges on the consolidated financial statements is depicted below (in thousands):



The Effect of Derivative Instruments on the Statement of Financial Performance
For the Three Months Ended
	Amount of Gain or (Loss) Recognized in OCI on Derivative (Effective Portion)				Location of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)						Location of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion )	Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion )

Derivatives in ASC 815 Cash Flow Hedging Relationships

	April 1, 2017		March 26, 2016				April 1, 2017			March 26, 2016				April 1, 2017		March 26, 2016
Interest rate contracts	$	120	$	—	Other income (expense), net		$	(37	)	$	—	Other income (expense), net		$	14	$	—
Total	$	120	$	—			$	(37	)	$	—			$	14	$	—

Inventories (Tables)

3 Months Ended

Apr. 01, 2017

Inventory Disclosure [Abstract]

Schedule of Inventory Components

Inventories consisted of the following (in thousands):



	April 1, 2017		December 31, 2016
Raw materials	$	29,009	$	27,402
Work-in-progress	19,625		20,390
Finished goods	11,737		12,014
	$	60,371	$	59,806

Warranty (Tables)

3 Months Ended

Apr. 01, 2017

Product Warranties Disclosures [Abstract]

Reconciliation of Changes in Warranty Liability

A reconciliation of the changes in our warranty liability for the three months ended April 1, 2017 and March 26, 2016, respectively, is as follows (in thousands):



	April 1, 2017			March 26, 2016
Balance at beginning of period	$	2,972		$	1,116
Accruals	1,127			805
Settlements	(1,517		)	(747		)
Balance at the end of period	$	2,582		$	1,174

Stockholders' Equity (Tables)

3 Months Ended

Apr. 01, 2017

Equity [Abstract]

Schedule of Restricted Stock Unit Activity

Restricted stock unit (RSU) activity under our equity incentive plan during the three months ended April 1, 2017 is set forth below:



	Units		Weighted Average Grant Date Fair Value
Restricted stock units at December 31, 2016	3,108,560		$	8.61
Awards granted	23,622		12.70
Awards vested	(94,608	)	3.51
Awards canceled	(102,721	)	8.70
Restricted stock units at April 1, 2017	2,934,853		$	8.81

Schedule of Stock Option Activity

Stock option activity under our equity incentive plan during the three months ended April 1, 2017 is set forth below:



	Options Outstanding		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life in Years	Aggregate Intrinsic Value
Outstanding at December 31, 2016	2,198,031		$	9.13
Options exercised	(560,950	)	8.09
Outstanding at April 1, 2017	1,637,081		$	9.48	2.23	$	4,073,803
Vested and expected to vest at April 1, 2017	1,637,081		$	9.48	2.23	$	4,073,803
Exercisable at April 1, 2017	1,355,147		$	9.84	1.58	$	2,915,206

Schedule of Stock-based Compensation

Stock-based compensation was included in our Condensed Consolidated Statements of Operations as follows (in thousands):



	Three Months Ended
	April 1, 2017		March 26, 2016

Cost of revenues	$	854	$	633
Research and development	1,082		796
Selling, general and administrative	1,366		1,305
Total stock-based compensation	$	3,302	$	2,734

Schedule of Unrecognized Stock-based Compensation

At April 1, 2017, the unrecognized stock-based compensation was as follows (in thousands):



	Unrecognized Expense		Average Expected Recognition Period in Years
Stock options	$	932	1.81
Restricted stock units	17,328		2.04
Employee stock purchase plan	687		0.33
Total unrecognized stock-based compensation expense	$	18,947

Net Income (Loss) per Share (Tables)

3 Months Ended

Apr. 01, 2017

Earnings Per Share [Abstract]

Schedule of Calculation of Numerator and Denominator in Earnings Per Share

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



	Three Months Ended
	April 1, 2017		March 26, 2016
Numerator:
Net income (loss) used in computing basic and diluted net income per share	$	5,185	$	(13,800	)
Denominator:
Weighted-average shares used in computing basic net income (loss) per share	71,423		58,431
Add potentially dilutive securities	1,499		—
Weighted-average shares used in computing basic and diluted net income (loss) per share	72,922		58,431
Securities not included as they would have been antidilutive	126		4,257

Operating Segments (Tables)

3 Months Ended

Apr. 01, 2017

Segment Reporting [Abstract]

Schedule of Operating Results by Segment

The following table summarizes the operating results by reportable segments for the three months ended April 1, 2017 and March 26, 2016 (in thousands, except percentages):



	Three Months Ended
	April 1, 2017												March 26, 2016
	Probe Cards			Systems			Corporate and Other			Total			Probe Cards			Systems			Corporate and Other			Total
Revenues	$	106,496		$	22,333		$	—		$	128,829		$	53,611		$	—		$	—		$	53,611
Gross profit	$	42,820		$	12,090		$	(7,339	)	$	47,571		$	12,509		$	—		$	(2,717	)	$	9,792
Gross margin	40.2		%	54.1		%	—		%	36.9		%	23.3		%	—		%	—		%	18.3		%
Operating income (loss)	$	21,742		$	5,122		$	(19,805	)	$	7,059		$	(2,029	)	$	—		$	(11,544	)	$	(13,573	)

Basis of Presentation and Summary of Significant Accounting Policies (Details) $ in Millions	Jan. 01, 2017 USD ($)
Retained Earnings \| Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accumulated deficit upon accounting policy adoption	$ 0.1

Concentration of Credit and Other Risks (Details) - Customer Concentration Risk	3 Months Ended		12 Months Ended
	Apr. 01, 2017	Mar. 26, 2016	Dec. 31, 2016
Revenues
Concentration Risk [Line Items]
Concentration risk percentage	37.00%	44.70%
Revenues \| Intel
Concentration Risk [Line Items]
Concentration risk percentage	26.70%	34.30%
Revenues \| Samsung
Concentration Risk [Line Items]
Concentration risk percentage	10.30%	10.40%
Accounts Receivable \| Major Customer 1
Concentration Risk [Line Items]
Concentration risk percentage	22.00%		21.00%

Acquisition (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill	$ 188,185	$ 188,010
Cascade Microtech
Business Acquisition [Line Items]
Cash and cash equivalents	40,681
Accounts receivable	27,112
Inventory	38,315
Prepaid expenses and other current assets	6,249
Property, plant and equipment	19,875
Other long-term assets	818
Deferred revenue	(1,829)
Accounts payable and accrued liabilities	(23,370)
Deferred tax liabilities	(48,993)
Other long-term liabilities	(960)
Total tangible assets acquired and liabilities assumed	57,898
Intangible assets	149,753
Goodwill	158,141
Total acquisition price	$ 365,792

Goodwill and Intangible Assets - Goodwill (Details)	3 Months Ended
Goodwill and Intangible Assets - Goodwill (Details)	Apr. 01, 2017 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 188,010,000
Foreign currency translation	175,000
Goodwill, ending balance	188,185,000
Goodwill impairment	0
Cascade Microtech
Goodwill [Roll Forward]
Goodwill, ending balance	158,141,000
MicroProbe Inc.
Goodwill [Roll Forward]
Goodwill, ending balance	30,700,000
Probe Cards
Goodwill [Roll Forward]
Goodwill, beginning balance	172,482,000
Foreign currency translation	0
Goodwill, ending balance	172,482,000
Systems
Goodwill [Roll Forward]
Goodwill, beginning balance	15,528,000
Foreign currency translation	175,000
Goodwill, ending balance	$ 15,703,000

Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 210,256	$ 210,072
Accumulated Amortization	91,812	83,463
Intangible Assets, Net	118,444	126,609
Existing developed technologies
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	142,824	142,701
Accumulated Amortization	61,258	56,131
Intangible Assets, Net	$ 81,566	86,570
Weighted Average Useful Life	4 years 1 month 6 days
Trade name
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 11,934	11,921
Accumulated Amortization	3,668	2,989
Intangible Assets, Net	$ 8,266	8,932
Weighted Average Useful Life	3 years 9 months 6 days
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 39,908	39,869
Accumulated Amortization	12,200	10,854
Intangible Assets, Net	$ 27,708	29,015
Weighted Average Useful Life	5 years 6 months 6 days
Backlog
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 15,590	15,581
Accumulated Amortization	14,686	13,489
Intangible Assets, Net	$ 904	$ 2,092
Weighted Average Useful Life	6 days

Goodwill and Intangible Assets - Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets, Net, Amortization Expense, Rolling Maturity [Abstract]
2017	$ 22,366
2018	28,339
2019	25,675
2020	23,605
2021	12,937
and thereafter	5,522
Intangible Assets, Net	118,444		$ 126,609
Cost of revenues
Property, Plant and Equipment [Line Items]
Amortization of intangible assets	6,300	$ 2,100
Selling, general and administrative
Property, Plant and Equipment [Line Items]
Amortization of intangible assets	$ 2,000	$ 600

Debt (Details) $ in Thousands	Apr. 01, 2017 USD ($)
Debt Disclosure [Abstract]
Senior secured term loan	$ 132,500
Debt issuance costs	(1,027)
Total debt less debt issuance costs	$ 131,473

Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended
Restructuring Charges (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Mar. 26, 2016
Restructuring Reserve [Roll Forward]
Accrual at beginning of period	$ 434
Restructuring charges	269	$ 0
Cash payments	(458)
Adjustment to restructuring charges	32
Accrual at end of period	277
Employee Severance and Benefits
Restructuring Reserve [Roll Forward]
Accrual at beginning of period	330
Restructuring charges	248
Cash payments	(423)
Adjustment to restructuring charges	32
Accrual at end of period	187
Contract Termination and Other Costs
Restructuring Reserve [Roll Forward]
Accrual at beginning of period	104
Restructuring charges	21
Cash payments	(35)
Adjustment to restructuring charges	0
Accrual at end of period	$ 90

Fair Value - Fair Value Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets measured at fair value	$ 27,894	$ 28,822
Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts		1,137
Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	1,009	838
Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	19,388	19,350
U.S. Treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	7,497	7,497
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets measured at fair value	19,388	19,350
Level 1 \| Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts		0
Level 1 \| Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	0	0
Level 1 \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	19,388	19,350
Level 1 \| U.S. Treasuries
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets measured at fair value	8,506	9,472
Level 2 \| Foreign exchange derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts		1,137
Level 2 \| Interest rate swap derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	1,009	838
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]
Marketable securities	$ 7,497	$ 7,497

Fair Value - Losses Related to Non-designated Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Derivatives Not Designated as Hedging Instruments \| Foreign exchange forward contracts \| Other income (expense), net
Derivatives, Fair Value [Line Items]
Amount of Loss Recognized on Derivatives	$ (886)	$ (1,562)

Fair Value - Interest Rate Swaps (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedge ineffectiveness recorded	$ 65
Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative (Effective Portion)	120	$ 0
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(37)	0
Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion )	14	0
Interest rate contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	1,009		$ 838
Designated as Hedging Instrument \| Interest rate contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	1,000
Designated as Hedging Instrument \| Interest rate contracts \| Cash Flow Hedging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivative (Effective Portion)	120	0
Designated as Hedging Instrument \| Interest rate contracts \| Cash Flow Hedging \| Other income (expense), net
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(37)	0
Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion )	$ 14	$ 0

Fair Value - Assets Measured at Fair Value on a Non-Recurring Basis (Details) - USD ($)	Apr. 01, 2017	Mar. 26, 2016
Fair Value Disclosures [Abstract]
Assets measured at fair value on non-recurring basis	$ 0	$ 0

Inventories (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw materials	$ 29,009	$ 27,402
Work-in-progress	19,625	20,390
Finished goods	11,737	12,014
Inventory, Net	$ 60,371	$ 59,806

Warranty (Details) - USD ($) $ in Thousands	3 Months Ended
Warranty (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Mar. 26, 2016
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Balance at beginning of period	$ 2,972	$ 1,116
Accruals	1,127	805
Settlements	(1,517)	(747)
Balance at the end of period	$ 2,582	$ 1,174

Stockholders' Equity - Additional Information (Details) - USD ($)	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016	Feb. 28, 2017	Apr. 16, 2015
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP (In shares)	397,024	303,585
Equity Incentive Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted stock units vested during the period	$ 1,200,000	$ 4,000,000
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program authorized amount			$ 25,000,000	$ 25,000,000.0
Stock repurchased during the period (In shares)	250,000
Stock repurchased during the period, amount	$ 2,700,000

Stockholders' Equity - Restricted Stock Unit Activity (Details) - Equity Incentive Plan - Restricted Stock Units	3 Months Ended
	Apr. 01, 2017 $ / shares shares
Units
Beginning balance (in shares) \| shares	3,108,560
Awards granted (in shares) \| shares	23,622
Awards vested (in shares) \| shares	(94,608)
Awards canceled (in shares) \| shares	(102,721)
Ending balance (in shares) \| shares	2,934,853
Weighted Average Grant Date Fair Value
Beginning Balance (in dollars per share) \| $ / shares	$ 8.61
Awards granted (in dollars per share) \| $ / shares	12.70
Awards vested (in dollars per share) \| $ / shares	3.51
Awards canceled (in dollars per share) \| $ / shares	8.70
Ending Balance (in dollars per share) \| $ / shares	$ 8.81

Stockholders' Equity - Stock Option Activity (Details) - Equity Incentive Plan	3 Months Ended
	Apr. 01, 2017 USD ($) $ / shares shares
Options Outstanding
Outstanding, beginning of period (In shares) \| shares	2,198,031
Options exercised (In shares) \| shares	(560,950)
Outstanding, end of period (In shares) \| shares	1,637,081
Vested and expected to vest (In shares) \| shares	1,637,081
Exercisable (In shares) \| shares	1,355,147
Weighted Average Exercise Price
Outstanding, beginning of period (In dollars per share) \| $ / shares	$ 9.13
Options exercised (In dollars per share) \| $ / shares	8.09
Outstanding, end of period (In dollars per share) \| $ / shares	9.48
Vested and expected to vest (In dollars per share) \| $ / shares	9.48
Exercisable (In dollars per share) \| $ / shares	$ 9.84
Additional Disclosures
Outstanding, weighted average remaining contractual life	2 years 2 months 22 days
Vested and expected to vest, weighted average remaining contractual life	2 years 2 months 22 days
Exercisable, weighted average remaining contractual life	1 year 6 months 28 days
Outstanding, aggregate intrinsic value \| $	$ 4,073,803
Vested and expected to vest, aggregate intrinsic value \| $	4,073,803
Exercisable, aggregate intrinsic value \| $	$ 2,915,206

Stockholders' Equity - Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 3,302	$ 2,734
Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	854	633
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	1,082	796
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	$ 1,366	$ 1,305

Stockholders' Equity - Unrecognized Compensation Costs (Details) $ in Thousands	3 Months Ended
	Apr. 01, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized stock-based compensation expense	$ 18,947
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, stock options	$ 932
Average expected recognition period	1 year 9 months 22 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than options	$ 17,328
Average expected recognition period	2 years 16 days
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than options	$ 687
Average expected recognition period	4 months

Net Income (Loss) per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Numerator:
Net income (loss) used in computing basic and diluted net income per share	$ 5,185	$ (13,800)
Denominator:
Weighted-average shares used in computing basic net income per share (In shares)	71,423	58,431
Add potentially dilutive securities (In shares)	1,499	0
Weighted-average shares used in computing basic and diluted net income per share (In shares)	72,922	58,431
Anti-dilutive securities (In shares)	126	4,257

Commitments and Contingencies (Details) - California Wage Law - USD ($) $ in Millions	Mar. 14, 2017	Apr. 01, 2017	Dec. 31, 2016
Loss Contingencies [Line Items]
Settlement amount	$ 1.5
Settlement accrual		$ 1.5	$ 1.5

Operating Segments - Additional Information (Details)	3 Months Ended
Operating Segments - Additional Information (Details)	Apr. 01, 2017 segment
Segment Reporting [Abstract]
Number of reportable segments	2

Operating Segments - Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Mar. 26, 2016
Segment Reporting Information [Line Items]
Revenues	$ 128,829	$ 53,611
Gross profit	$ 47,571	$ 9,792
Gross margin	36.90%	18.30%
Operating income (loss)	$ 7,059	$ (13,573)
Operating Segments \| Probe Cards
Segment Reporting Information [Line Items]
Revenues	106,496	53,611
Gross profit	$ 42,820	$ 12,509
Gross margin	40.20%	23.30%
Operating income (loss)	$ 21,742	$ (2,029)
Operating Segments \| Systems
Segment Reporting Information [Line Items]
Revenues	22,333	0
Gross profit	$ 12,090	$ 0
Gross margin	54.10%	0.00%
Operating income (loss)	$ 5,122	$ 0
Corporate and Other
Segment Reporting Information [Line Items]
Revenues	0	0
Gross profit	(7,339)	(2,717)
Operating income (loss)	$ (19,805)	$ (11,544)