Cognex (CGNX) 10-Q 28 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 29, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	29-Sep-13
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Entity Registrant Name	COGNEX CORP
Entity Central Index Key	851205
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	87,280,585

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended				9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 29, 2013		Sep. 30, 2012		Sep. 29, 2013		Sep. 30, 2012
Revenue
Product	$83,464		$72,437		$237,834		$222,293
Service	7,324		7,639		20,356		19,818
Total revenue	90,788		80,076		258,190		242,111
Cost of revenue
Product	18,132		15,863		52,506		49,054
Service	3,216		3,643		9,415		10,059
Total cost of revenue	21,348		19,506		61,921		59,113
Gross margin
Product	65,332		56,574		185,328		173,239
Service	4,108		3,996		10,941		9,759
Total gross margin	69,440		60,570		196,269		182,998
Research, development, and engineering expenses	12,184		10,002		35,392		30,663
Selling, general, and administrative expenses	33,877		28,765		99,344		89,441
Operating income	23,379		21,803		61,533		62,894
Foreign currency loss	-442		-409		-303		-1,077
Investment income	937		823		2,103		3,596
Other expense	-166		-131		-306		-227
Income before income tax expense	23,708		22,086		63,027		65,186
Income tax expense	2,981		4,281		9,987		13,332
Net income	$20,727		$17,805		$53,130		$51,854
Earnings per weighted-average common and common-equivalent share:
Basic	$0.24	[1]	$0.21	[1]	$0.61	[1]	$0.61	[1]
Diluted	$0.23	[1]	$0.20	[1]	$0.59	[1]	$0.59	[1]
Weighted-average common and common-equivalent shares outstanding:
Basic	87,339	[1]	85,824	[1]	87,578	[1]	85,554	[1]
Diluted	89,359	[1]	87,258	[1]	89,450	[1]	87,220	[1]
Cash dividends per common share	$0	[1]	$0.06	[1]	$0	[1]	$0.16	[1]
[1]	Prior period results have been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend which occurred in September 2013.

Consolidated_Statements_of_Ope1

Consolidated Statements of Operations (Parenthetical)	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 29, 2013	Sep. 29, 2013	Sep. 29, 2013
Income Statement [Abstract]
Stock split conversion ratio	2	2	2

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net income	$20,727	$17,805	$53,130	$51,854
Other comprehensive income (loss), net of tax:
Net unrealized gain (loss) on available-for-sale investments, net of tax of $152 and $102 in the three-month periods and net of tax of ($124) and $302 in the nine-month periods, respectively	764	523	-342	2,141
Foreign currency translation adjustments, net of tax of $302 and $17 in the three-month periods and net of tax of $121 and ($180) in the nine-month periods, respectively	1,626	-2,905	-181	-12,086
Other comprehensive income (loss)	2,390	-2,382	-523	-9,945
Total comprehensive income	$23,117	$15,423	$52,607	$41,909

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]
Tax effect of unrealized gain (loss) on available-for-sale investments	$152	$102	($124)	$302
Tax effect of foreign currency translation adjustment	$302	$17	$121	($180)

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 29, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$30,446		$45,160
Short-term investments	186,572		105,105
Accounts receivable, less reserves of $1,346 and $1,131 in 2013 and 2012, respectively	48,832		42,387
Inventories	27,625		26,182
Deferred income taxes	6,292		6,369
Prepaid expenses and other current assets	19,300		14,394
Total current assets	319,067		239,597
Long-term investments	226,720		238,255
Property, plant, and equipment, net	35,565		34,820
Deferred income taxes	15,503		15,647
Intangible assets, net	11,890		14,770
Goodwill	81,689		81,689
Other assets	2,316		2,827
Total assets	692,750		627,605
Current liabilities:
Accounts payable	7,457		6,815
Accrued expenses	31,367		29,590
Accrued income taxes	90		1,009
Deferred revenue and customer deposits	11,722		12,690
Total current liabilities	50,636		50,104
Reserve for income taxes	4,390		5,216
Commitments and contingencies (Note 8)
Shareholders' equity:
Common stock, $.002 par value - Authorized: 140,000 shares, issued: 87,281 and 86,110 shares in 2013 and 2012, respectively	175	[1]	172	[1]
Additional paid-in capital	206,152	[1]	165,162	[1]
Retained earnings	461,538	[1]	436,466	[1]
Accumulated other comprehensive loss, net of tax	-30,141	[1]	-29,515	[1]
Total shareholders' equity	637,724	[1]	572,285	[1]
Total liabilities and shareholders' equity	$692,750		$627,605
[1]	Prior period amounts have been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend which occurred in September 2013.

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 29, 2013		Dec. 31, 2012
In Thousands, except Per Share data, unless otherwise specified
Statement Of Financial Position [Abstract]
Reserves for accounts receivable	$1,346		$1,131
Common stock, par value	$0.00		$0.00
Common stock, shares authorized	140,000		140,000
Common stock, shares issued	87,281	[1]	86,110	[1]
[1]	Prior period amounts have been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend which occurred in September 2013.

Consolidated_Statement_of_Shar

Consolidated Statement of Shareholders' Equity (USD $)	Total		Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
In Thousands
Beginning Balance at Dec. 31, 2012	$572,285	[1]	$172	$165,162	$436,466	($29,515)
Beginning Balance, Shares at Dec. 31, 2012	86,110	[1]	86,110
Issuance of common stock under stock option plans	25,990		4	25,986
Issuance of common stock under stock option plans, shares	2,275		2,270
Repurchase of common stock	-28,059		-1		-28,058
Repurchase of common stock, shares			-1,099
Stock-based compensation expense	8,299			8,299
Excess tax benefit from stock option exercises	6,584			6,584
Tax benefit for research and development credits as a result of stock option accounting	121			121
Net income	53,130				53,130
Net unrealized loss on available-for-sale investments, net of tax of $124	-342					-342
Reclassification of net realized gain on the sale of available-for-sale investments	-103					-103
Foreign currency translation adjustment, net of tax of $121	-181					-181
Ending Balance at Sep. 29, 2013	$637,724	[1]	$175	$206,152	$461,538	($30,141)
Ending Balance, Shares at Sep. 29, 2013	87,281	[1]	87,281
[1]	Prior period amounts have been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend which occurred in September 2013.

Consolidated_Statement_of_Shar1

Consolidated Statement of Shareholders' Equity (Parenthetical) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013
Tax effect of unrealized loss on available-for-sale investments	$124
Tax effect of foreign currency translation adjustment	121
Accumulated Other Comprehensive Loss [Member]
Tax effect of unrealized loss on available-for-sale investments	124
Tax effect of foreign currency translation adjustment	$121

Consolidated_Condensed_Stateme

Consolidated Condensed Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$53,130	$51,854
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation expense	8,299	6,795
Depreciation of property, plant, and equipment	5,389	4,977
Amortization of intangible assets	2,880	3,124
Amortization of discounts or premiums on investments	1,996	4,719
Realized gain on sale of investments	-103	-1,411
Tax effect of stock option exercises	-6,584	-3,256
Change in deferred income taxes	216	-1,509
Net unrealized loss on trading securities	267
Change in operating assets and liabilities	-6,255	9,516
Net cash provided by operating activities	59,235	74,809
Cash flows from investing activities:
Purchases of investments	-251,033	-355,351
Maturities and sales of investments	178,372	309,081
Purchases of property, plant, and equipment	-6,152	-7,621
Net cash used in investing activities	-78,813	-53,891
Cash flows from financing activities:
Issuance of common stock under stock option plans	25,990	15,579
Repurchase of common stock	-28,059
Payment of dividends		-13,706
Tax effect of stock option exercises	6,584	3,256
Net cash provided by financing activities	4,515	5,129
Effect of foreign exchange rate changes on cash and cash equivalents	349	-9,992
Net change in cash and cash equivalents	-14,714	16,055
Cash and cash equivalents at beginning of period	45,160	38,103
Cash and cash equivalents at end of period	$30,446	$54,158

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 29, 2013
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	NOTE 1: Summary of Significant Accounting Policies
	As permitted by the rules of the Securities and Exchange Commission applicable to Quarterly Reports on Form 10-Q, these notes are condensed and do not contain all disclosures required by generally accepted accounting principles (GAAP). Reference should be made to the consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012.
	In the opinion of the management of Cognex Corporation (the “Company”), the accompanying consolidated unaudited financial statements contain all adjustments, consisting of normal, recurring adjustments and financial statement reclassifications necessary to present fairly the Company’s financial position as of September 29, 2013, and the results of its operations for the three-month and nine-month periods ended September 29, 2013 and September 30, 2012, and changes in shareholders’ equity, comprehensive income, and cash flows for the periods presented.
	On July 29, 2013, the Company’s Board of Directors declared a two-for-one split of the Company’s common stock, which was effected through a stock dividend distributed on September 16, 2013. All references made to share or per share amounts in the accompanying consolidated financial statements and applicable disclosures have been restated to reflect the effect of this two-for-one stock split for all periods presented.
	The results disclosed in the Consolidated Statements of Operations for the three-month and nine-month periods ended September 29, 2013 are not necessarily indicative of the results to be expected for the full year.

New_Pronouncements

New Pronouncements	9 Months Ended
	Sep. 29, 2013
Accounting Changes And Error Corrections [Abstract]
New Pronouncements	NOTE 2: New Pronouncements
	Accounting Standards Update (ASU) 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities”
	The amendments in ASU 2013-01 require companies to present enhanced disclosure about certain financial instruments and derivative instruments that are offset in the balance sheet or subject to an enforceable master netting arrangement or similar agreement. The disclosure requirement became effective, retrospectively, in the first quarter of our fiscal year ending December 31, 2013. However, as this ASU related only to presentation and disclosure it did not have an impact on our consolidated financial position, results of operations, or cash flows.
	Accounting Standards Update (ASU) 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income”
	The amendments in ASU 2013-02 require companies to present information about amounts reclassified out of accumulated other comprehensive income (OCI) to net income, by component. The effect of significant reclassification adjustments being made out of accumulated OCI on the corresponding line items in net income must be presented when the item is reclassified in its entirety during one reporting period. While the new guidance in ASU 2013-12 changes the presentation of accumulated OCI, there are no changes to the components that are recognized in net income or OCI under current accounting guidance.
	Amounts reclassified from accumulated other comprehensive income to investment income on the Consolidated Statements of Operations were realized gains of $20,000 and $103,000 during the three-month and nine-month periods ended September 29, 2013, respectively, and realized gains of $340,000 and $1,411,000 during the three-month and nine-month periods ended September 30, 2012, respectively.
	Accounting Standards Update (ASU) 2013-11, “Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists”
	The amendments in ASU 2013-11 require companies to present an unrecognized tax benefit, or a portion thereof, as a reduction to a deferred tax asset for a net operating loss (NOL) carryforward or a similar tax loss or tax credit carryforward, unless the uncertain tax position is not available to reduce, or would not be used to reduce, the NOL or carryforward under the tax law in the same jurisdiction; otherwise, the unrecognized tax benefit should be presented as a gross liability and should not net the unrecognized tax benefit with a deferred tax asset. As the Company does not currently have any NOL carryforwards, this guidance will most likely apply to research and development tax credit carryforwards. ASU 2013-11 is effective for annual periods beginning after December 15, 2013 and should be applied to all unrecognized tax benefits that exist as of the effective date. Companies may choose to apply this guidance retrospectively to each prior reporting period presented. Management is the process of evaluating the impact of this Update.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 29, 2013
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE 3: Fair Value Measurements
	Financial Assets and Liabilities that are Measured at Fair Value on a Recurring Basis
	The following table summarizes the financial assets and liabilities required to be measured at fair value on a recurring basis as of September 29, 2013 (in thousands):
		Quoted Prices in		Significant Other
		Active Markets		Observable
		for Identical		Inputs (Level 2)
		Assets (Level 1)
	Assets:
	Corporate stock	$	1,864	$	—
	Money market instruments		225		—
	Corporate bonds		—		210,341
	Asset-backed securities		—		69,928
	Treasury bills		—		69,277
	Sovereign bonds		—		29,923
	Municipal bonds		—		28,005
	Agency bonds		—		1,499
	Currency forward contracts		—		81
	Liabilities:
	Currency forward contracts		—		64
	The Company’s cash equivalents and money market instruments are reported at fair value based upon the daily market price for identical assets in active markets, and are therefore classified as Level 1 investments. The Company’s corporate stock position is reported at fair value based upon quoted market prices on a stock exchange, and is therefore classified as a Level 1 investment.
	The Company’s debt securities and currency forward contracts are reported at fair value based upon model-driven valuations in which all significant inputs are observable or can be derived from or corroborated by observable market data for substantially the full term of the asset, and are therefore classified as Level 2 investments. Management is responsible for estimating the fair value of these financial assets and liabilities, and in doing so, considers valuations provided by a large, third-party pricing service. For debt securities, this service maintains regular contact with market makers, brokers, dealers, and analysts to gather information on market movement, direction, trends, and other specific data. They use this information to structure yield curves for various types of debt securities and arrive at the daily valuations.
	The Company did not record an other-than-temporary impairment of these investments during the nine-month period ended September 29, 2013.
	Financial Assets that are Measured at Fair Value on a Non-recurring Basis
	The Company has an interest in a limited partnership, which is accounted for using the cost method and is required to be measured at fair value on a non-recurring basis. Management is responsible for estimating the fair value of this investment, and in doing so, considers valuations of the partnership’s investments as determined by the General Partner. Publicly-traded investments in active markets are reported at the market closing price less a discount, as appropriate, to reflect restricted marketability. Fair value for private investments for which observable market prices in active markets do not exist is based upon the best information available including the value of a recent financing, reference to observable valuation measures for comparable companies (such as revenue multiples), public or private transactions (such as the sale of a comparable company), and valuations for publicly-traded comparable companies. The valuations also incorporate the General Partner’s own judgment and close familiarity with the business activities of each portfolio company. Significant increases or decreases in any of these inputs in isolation may result in a significantly lower or higher fair value measurement. The portfolio consists of securities of public and private companies, and consequently, inputs used in the fair value calculation are classified as Level 3. The Company did not record an other-than-temporary impairment of this asset during the nine-month period ended September 29, 2013.
	Non-financial Assets that are Measured at Fair Value on a Non-recurring Basis
	Non-financial assets such as goodwill, intangible assets, and property, plant, and equipment are required to be measured at fair value only when an impairment loss is recognized. The Company did not record an impairment charge related to these assets during the nine-month period ended September 29, 2013.

Cash_Cash_Equivalents_and_Inve

Cash, Cash Equivalents, and Investments	9 Months Ended
	Sep. 29, 2013
Cash And Cash Equivalents [Abstract]
Cash, Cash Equivalents, and Investments	NOTE 4: Cash, Cash Equivalents, and Investments
	Cash, cash equivalents, and investments consisted of the following (in thousands):
		September 29,		December 31,
		2013		2012
	Cash	$	30,221	$	34,986
	Cash equivalents		—		5,098
	Money market instruments		225		5,076
	Cash and cash equivalents		30,446		45,160
	Corporate bonds		104,720		46,001
	Asset-backed securities		41,269		17,666
	Municipal bonds		17,013		16,224
	Treasury bills		11,654		5,997
	Sovereign bonds		8,553		3,986
	Corporate stock		1,864		2,131
	Agency bonds		1,499		7,482
	Covered bonds		—		5,618
	Short-term investments		186,572		105,105
	Corporate bonds		105,621		100,072
	Treasury bills		57,623		36,276
	Asset-backed securities		28,659		34,710
	Sovereign bonds		21,370		10,606
	Municipal bonds		10,992		17,846
	Agency bonds		—		29,441
	Covered bonds		—		5,564
	Limited partnership interest (accounted for using cost method)		2,455		3,740
	Long-term investments		226,720		238,255
		$	443,738	$	388,520
	The Company’s investment portfolio includes corporate bonds, asset-backed securities, treasury bills, sovereign bonds, municipal bonds, and agency bonds. Corporate bonds consist of debt securities issued by both domestic and foreign companies; asset-backed securities consist of debt securities collateralized by pools of receivables or loans with credit enhancement; treasury bills consist of debt securities issued by both the U.S. and foreign governments; sovereign bonds consist of direct debt issued by foreign governments; municipal bonds consist of debt securities issued by state and local government entities; and agency bonds consist of domestic or foreign obligations of government agencies and government sponsored enterprises that have government backing.
	The following tables summarize the Company’s available-for-sale investments as of September 29, 2013 (in thousands):
		Amortized		Gross			Gross			Fair Value
		Cost		Unrealized			Unrealized
				Gains			Losses
	Short-term:
	Corporate bonds	$	104,580	$	270		$	(130	)	$	104,720
	Asset-backed securities		41,600		7			(338	)		41,269
	Municipal bonds		16,969		44			—			17,013
	Treasury bills		11,647		7			—			11,654
	Sovereign bonds		8,554		9			(10	)		8,553
	Agency bonds		1,500		—			(1	)		1,499
	Long-term:
	Corporate bonds		105,251		513			(143	)		105,621
	Treasury bills		57,604		24			(5	)		57,623
	Asset-backed securities		28,810		10			(161	)		28,659
	Sovereign bonds		21,386		57			(73	)		21,370
	Municipal bonds		10,957		45			(10	)		10,992
		$	408,858	$	986		$	(871	)	$	408,973
	The following table summarizes the Company’s gross unrealized losses and fair values for available-for-sale investments in an unrealized loss position as of September 29, 2013 (in thousands):
		Unrealized Loss Position For:
		Less than 12 Months					12 Months or Greater						Total
		Fair Value		Unrealized			Fair Value			Unrealized			Fair Value		Unrealized
				Losses						Losses					Losses
	Corporate bonds	$	62,910	$	(272	)	$	2,455		$	(1	)	$	65,365	$	(273	)
	Asset- backed securities		41,848		(102	)		16,332			(397	)		58,180		(499	)
	Sovereign bonds		9,300		(25	)		888			(58	)		10,188		(83	)
	Treasury bills		7,614		(5	)		—			—			7,614		(5	)
	Municipal bonds		4,374		(10	)		—			—			4,374		(10	)
	Agency bonds		1,499		(1	)		—			—			1,499		(1	)
		$	127,545	$	(415	)	$	19,675		$	(456	)	$	147,220	$	(871	)
	As of September 29, 2013, the Company did not recognize an other-than-temporary impairment of these investments. In its evaluation, management considered the type of security, the credit rating of the security, the length of time the security has been in a loss position, the size of the loss position, our intent and ability to hold the security to expected recovery of value, and other meaningful information. The Company does not intend to sell, and is unlikely to be required to sell, any of these available-for-sale investments before its effective maturity or market price recovery.
	The Company recorded gross realized gains and gross realized losses on the sale of investments totaling $32,000 and $12,000, respectively, during the three-month period ended September 29, 2013 and $342,000 and $1,000, respectively, during the three-month period ended September 30, 2012. The Company recorded gross realized gains and gross realized losses of $182,000 and $79,000, respectively, during the nine-month period ending September 29, 2013, and $1,669,000 and $239,000, respectively, during the nine-month period ended September 30, 2012.
	The following table presents the effective maturity dates of the Company’s available-for-sale investments as of September 29, 2013 (in thousands):
		<1		2-Jan			3-Feb			4-Mar			5-Apr		Total
		Year		Years			Years			Years			Years
	Corporate bonds	$	104,720	$	61,596		$	41,299		$	2,203		$	523	$	210,341
Asset-backed securities		41,269		28,659			—			—			—		69,928
Treasury bills		11,654		48,015			9,608			—			—		69,277
Sovereign bonds		8,553		9,571			10,911			—			888		29,923
Municipal bonds		17,013		4,576			4,531			1,385			500		28,005
Agency bonds		1,499		—			—			—			—		1,499
	$	184,708	$	152,417		$	66,349		$	3,588		$	1,911	$	408,973
During the fourth quarter of 2012, the Company purchased equity securities, representing stock in a publicly-traded U.S. company, with an aggregate fair value of $2,131,000 as of December 31, 2012. As of September 29, 2013, these securities had an aggregate fair value of $1,864,000, resulting in a net unrealized loss of $267,000.
The Company is a Limited Partner in Venrock Associates III, L.P. (Venrock), a venture capital fund. The Company has committed to a total investment in the limited partnership of up to $20,500,000, with an expiration date of December 31, 2013. As of September 29, 2013, the Company contributed $19,886,000 to the partnership. The remaining commitment of $614,000 can be called by Venrock at any time before December 31, 2013. Distributions and contributions are at the discretion of Venrock’s management. No contributions were made during the nine-month period ended September 29, 2013. The Company received a cash distribution of $1,285,000 during the second quarter of 2013, which was accounted for as a return of capital.

Inventories

Inventories	9 Months Ended
	Sep. 29, 2013
Inventory Disclosure [Abstract]
Inventories	NOTE 5: Inventories
	Inventories consisted of the following (in thousands):
		September 29,		December 31,
		2013		2012
	Raw materials	$	14,050	$	12,667
	Work-in-process		3,935		4,193
	Finished goods		9,640		9,322
		$	27,625	$	26,182

Intangible_Assets_and_Goodwill

Intangible Assets and Goodwill	9 Months Ended
	Sep. 29, 2013
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible Assets and Goodwill	NOTE 6: Intangible Assets and Goodwill
	The Company evaluates the possible impairment of goodwill and other intangible assets whenever events or circumstances indicate that the carrying value of these assets may not be recoverable. No triggering event occurred in the nine-month period ended September 29, 2013 that would indicate a potential impairment of goodwill or other intangible assets. However, the Company continues to monitor a variety of factors that could result in an impairment of goodwill or other intangible assets in a future period.

Warranty_Obligations

Warranty Obligations	9 Months Ended
	Sep. 29, 2013
Guarantees [Abstract]
Warranty Obligations	NOTE 7: Warranty Obligations
	The Company records the estimated cost of fulfilling product warranties at the time of sale based upon historical costs to fulfill claims. Obligations may also be recorded subsequent to the time of sale whenever specific events or circumstances impacting product quality become known that would not have been taken into account using historical data. While we engage in extensive product quality programs and processes, including actively monitoring and evaluating the quality of our component suppliers and third-party contract manufacturers, the Company’s warranty obligation is affected by product failure rates, material usage, and service delivery costs incurred in correcting a product failure. An adverse change in any of these factors may result in the need for additional warranty provisions. Warranty obligations are included in “Accrued expenses” on the Consolidated Balance Sheets.
	The changes in the warranty obligations were as follows (in thousands):
	Balance as of December 31, 2012	$	2,256
	Provisions for warranties issued during the period		2,027
	Fulfillment of warranty obligations		(1,535	)
	Foreign exchange rate changes		64
	Balance as of September 29, 2013	$	2,812

Contingencies

Contingencies	9 Months Ended
	Sep. 29, 2013
Commitments And Contingencies Disclosure [Abstract]
Contingencies	NOTE 8: Contingencies
	In May 2008, the Company filed a complaint against MvTec Software GmbH, MvTec LLC, and Fuji America Corporation in the United States District Court for the District of Massachusetts alleging infringement of certain patents owned by the Company. This matter is ongoing.
	In May 2009, the Company pre-filed a complaint with the United States International Trade Commission (ITC) pursuant to Section 337 of the Tariff Act of 1930, as amended, 19 U.S.C. §1337, against MvTec Software GmbH, MvTec LLC, Fuji America, and several other respondents alleging unfair methods of competition and unfair acts in the unlawful importation into the United States, sale for importation, or sale within the United States after importation. By this filing, the Company requested the ITC to investigate the Company’s contention that certain machine vision software, machine vision systems, and products containing the same infringe, and respondents directly infringe and/or actively induce and/or contribute to the infringement in the United States, of one or more of the Company’s U.S. patents. In July 2009, the ITC issued an order that it would institute an investigation based upon the Company’s assertions. In September 2009, the Company reached a settlement with two of the respondents, and in December 2009, the Company reached a settlement with five additional respondents. In March 2010, the Company reached a settlement with respondent Fuji Machine Manufacturing Co., Ltd. and its subsidiary Fuji America Corporation. These settlements did not have a material impact on the Company’s financial results. An ITC hearing was held in May 2010. In July 2010, the Administrative Law Judge issued an initial determination finding two of the Company’s patents invalid and that respondents did not infringe the patents-at-issue. In September 2010, the ITC issued a notice that it would review the initial determination of the Administrative Law Judge. The ITC issued its Final Determination in November 2010 in which it determined to modify-in-part and affirm-in-part the Administrative Law Judge’s determination, and terminate the investigation with a finding of no violation of Section 337 of the Tariff Act of 1930 (as amended 19 U.S.C. §1337). The Company has filed an appeal of the decision with the United States Court of Appeals for the Federal Circuit. An oral hearing before the United States Court of Appeals occurred in February 2012. This matter is ongoing.
	In March 2013, the Company filed a lawsuit against Microscan Systems, Inc. (“Microscan”) and Code Corporation in the United States District Court for the Southern District of New York alleging that Microscan’s Mobile Hawk handheld imager infringes U.S. Patent 7,874,487 owned by the Company. The lawsuit seeks to prohibit Code Corporation from manufacturing the product, and Microscan from selling and distributing the product. The Company is also seeking monetary damages resulting from the alleged infringement. Both parties have filed motions for summary judgment and a hearing on these motions was held in October 2013. Trial was originally scheduled for October 2013, but has been moved to February 2014 at the earliest. This matter is ongoing.
	The Company cannot predict the outcome of the above-referenced pending matters and an adverse resolution of these lawsuits could have a material adverse effect on the Company’s financial position, liquidity, results of operations, and/or indemnification obligations. In addition, various other claims and legal proceedings generally incidental to the normal course of business are pending or threatened on behalf of or against the Company. While we cannot predict the outcome of these incidental matters, we believe that any liability arising from them will not have a material adverse effect on our financial position, liquidity, or results of operations.

Guarantees

Guarantees	9 Months Ended
	Sep. 29, 2013
Guarantees [Abstract]
Guarantees	NOTE 9: Guarantees
	In the ordinary course of business, the Company enters into guarantee contracts with certain customers, generally in the Company’s Surface Inspection Systems Division (SISD) business. These guarantees represent standby letters of credit (LOC) which can be grouped into three categories: (1) bank guarantees which may require the Company to return a customer’s initial payment if the Company cannot deliver the order; (2) warranty bonds which may require the Company to resolve warranty issues within a specified time period; and (3) performance bonds which include a combination of the above two options. The type of LOC is generally determined based upon customer request and the guarantee amount represents the maximum potential amount of future payments. All of the Company’s LOCs are with the same counterparty and they do not contain any recourse provisions or collateral obligations.
	The following table details the letters of credit outstanding as of September 29, 2013:
	Type	Guarantee		Guarantee due date
		Amount
		(in thousands)
	Bank Guarantees	$	294	Various from October 2013 to November 2013
	Performance Bonds		159	Various from January 2015 to March 2016
	Warranty Bonds		1,095	Various from October 2013 to August 2015
		$	1,548
	The Company evaluates losses for guarantees under accounting for contingencies. The Company considers such factors as the degree of probability that the Company would be required to satisfy the liability and the ability to make a reasonable estimate of the loss. To date, the Company has not incurred any losses as a result of these obligations, and therefore, has not recorded any liability related to such obligation in its financial statements. The fair value of the Company’s outstanding guarantees is immaterial for all periods presented.

Indemnification_Provisions

Indemnification Provisions	9 Months Ended
	Sep. 29, 2013
Text Block [Abstract]
Indemnification Provisions	NOTE 10: Indemnification Provisions
	Except as limited by Massachusetts law, the by-laws of the Company require it to indemnify certain current or former directors, officers, and employees of the Company against expenses incurred by them in connection with each proceeding in which he or she is involved as a result of serving or having served in certain capacities. Indemnification is not available with respect to a proceeding as to which it has been adjudicated that the person did not act in good faith in the reasonable belief that the action was in the best interests of the Company. The maximum potential amount of future payments the Company could be required to make under these provisions is unlimited. The Company has never incurred significant costs related to these indemnification provisions. As a result, the Company believes the estimated fair value of these provisions is minimal.
	In the ordinary course of business, the Company may accept standard limited indemnification provisions in connection with the sale of its products, whereby it indemnifies its customers for certain direct damages incurred in connection with third-party patent or other intellectual property infringement claims with respect to the use of the Company’s products. The term of these indemnification provisions generally coincides with the customer’s use of the Company’s products. The maximum potential amount of future payments the Company could be required to make under these provisions is generally subject to fixed monetary limits. The Company has never incurred significant costs to defend lawsuits or settle claims related to these indemnification provisions. As a result, the Company believes the estimated fair value of these provisions is minimal.
	In the ordinary course of business, the Company also accepts limited indemnification provisions from time to time, whereby it indemnifies customers for certain direct damages incurred in connection with bodily injury and property damage arising from the installation of the Company’s products. The term of these indemnification provisions generally coincides with the period of installation. The maximum potential amount of future payments the Company could be required to make under these provisions is generally limited and is likely recoverable under the Company’s insurance policies. As a result of this coverage, and the fact that the Company has never incurred significant costs to defend lawsuits or settle claims related to these indemnification provisions, the Company believes the estimated fair value of these provisions is minimal.

Derivative_Instruments

Derivative Instruments	9 Months Ended
	Sep. 29, 2013
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative Instruments	NOTE 11: Derivative Instruments
	The Company is exposed to certain risks relating to its ongoing business operations including foreign currency exchange rate risk and interest rate risk. The Company currently mitigates certain foreign currency exchange rate risks with derivative instruments. The Company does not currently manage its interest rate risk with derivative instruments.
	The Company faces exposure to foreign currency exchange rate fluctuations, as a significant portion of its revenues, expenses, assets, and liabilities are denominated in currencies other than the functional currencies of the Company’s subsidiaries or the reporting currency of the Company, which is the U.S. Dollar. The Company faces two types of foreign currency exchange rate exposures:
		•		Transactional currency/functional currency exchange rate exposures from transactions that are denominated in currencies other than the functional currency of the subsidiary. These transactions gains and losses are reported on the Consolidated Statements of Operations as a component of “Foreign Currency Gain (Loss).”
		•		Functional currency/reporting currency exchange rate exposures from the revaluation of the assets and liabilities of our foreign subsidiaries, whose functional currency is generally their local currency, to the Company’s reporting currency, which is the U.S. Dollar. The net effect of these translation gains and losses are reported in “Accumulated Other Comprehensive Loss” on the Consolidated Balance Sheets, and also on the Consolidated Statements of Comprehensive Income.
	The Company’s foreign currency risk management strategy is principally designed to mitigate the potential financial impact of changes in the value of transactions and balances denominated in foreign currencies resulting from changes in foreign currency exchange rates. Derivative instruments, specifically foreign currency forward contracts with maturities of up to three months, are used to manage the exposure to fluctuations in foreign currency exchange rates that arise primarily from foreign-denominated receivables and payables. As of September 29, 2013, the Company’s forward contracts do not qualify for effective hedge accounting. Because forward contracts are used as an economic hedge, any gain or loss on the underlying foreign-denominated balance is intended to be offset by the loss or gain on the forward contract. Gains and losses on forward contracts and foreign-denominated receivables and payables are included in “Foreign Currency Gain (Loss)” on the Consolidated Statements of Operations. The Company recorded net foreign currency losses of $442,000 and $303,000 in the three-month and nine-month periods ended September 29, 2013, respectively, and net foreign currency losses of $409,000 and $1,077,000 in the three-month and nine-month periods ended September 30, 2012, respectively.
	As of September 29, 2013, the Company had the following outstanding forward contracts that were entered into to mitigate foreign currency exchange rate risk (in thousands):
	Currency		Notional				USD
			Value				Equivalent
	Chinese Renminbi			20,000			$	3,213
	Japanese Yen			235,400				2,395
	Singapore Dollar			3,025				2,379
	Euro			1,035				1,400
	British Pound			650				1,036
	Korean Won			1,121,500				1,029
	Taiwanese Dollar			28,450				952
	Swedish Krona			5,800				891
	Hungarian Forint			135,000				603
	Information regarding the fair value of the forward contracts outstanding as of September 29, 2013 and December 31, 2012 was as follows (in thousands):
			Asset Derivatives									Liability Derivatives
			Balance		Fair Value							Balance	Fair Value
			Sheet		September 29,				December 31,			Sheet	September 29,		December 31,
			Location		2013				2012			Location	2013		2012
	Currency forward contracts		Prepaid expenses and		$	81			$	44		Accrued	$	64	$	14
			other current assets									expenses
	Information regarding the effect of the forward contracts, net of the underlying exposure, on the Consolidated Statements of Operations for the three-month and nine-month periods ended September 29, 2013 and September 30, 2012 was as follows (in thousands):
					Amount of Loss Recognized								Amount of Gain (Loss)
													Recognized
			Location of		Three-months ended							Location of	Nine-months ended
			Loss		September 29,				September 30,			Gain (Loss)	September 29,		September 30,
			Recognized		2013				2012			Recognized	2013		2012
	Currency forward contracts		Foreign currency		$	(186	)		$	(546	)	Foreign currency	$	10	$	(637	)
			loss									gain (loss)

StockBased_Compensation_Expens

Stock-Based Compensation Expense	9 Months Ended
	Sep. 29, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation Expense	NOTE 12: Stock-Based Compensation Expense
	The Company’s share-based payments that result in compensation expense consist solely of stock option grants. As of September 29, 2013, the Company had 11,178,930 shares available for grant under two stock option plans: the 2001 General Stock Option Plan (8,660,710) and the 2007 Stock Option and Incentive Plan (2,518,220). Each of these plans expires ten years from the date the plan was approved. In December 2011, the 2001 General Stock Option Plan received shareholder approval for an amendment and restatement of the plan, extending the plan until September 2021. Generally, stock options are granted with an exercise price equal to the market value of the Company’s common stock at the grant date, vest over four years based upon continuous service, and expire ten years from the grant date.
	The following table summarizes the Company’s stock option activity for the nine-month period ended September 29, 2013:
			Shares			Weighted-			Weighted-			Aggregate
			(in thousands)			Average			Average			Intrinsic
						Exercise			Remaining			Value
						Price			Contractual			(in thousands)
									Term (in years)
	Outstanding as of December 31, 2012			7,118		$	12.78
	Granted			1,711			21.29
	Exercised			(2,275	)		11.42
	Forfeited or expired			(259	)		16.29
	Outstanding as of September 29, 2013			6,295		$	15.44			7.4		$	100,525
	Exercisable as of September 29, 2013			1,806		$	11.55			5.4		$	35,855
	Options vested or expected to vest at September 29, 2013 (1)			5,577		$	15.09			7.2		$	91,041
	-1	In addition to the vested options, the Company expects a portion of the unvested options to vest at some point in the future. Options expected to vest are calculated by applying an estimated forfeiture rate to the unvested options.
	The fair values of stock options granted in each period presented were estimated using the following weighted-average assumptions:
			Three-months Ended						Nine-months Ended
			September 29,			September 30,			September 29,			September 30,
			2013			2012			2013			2012
	Risk-free rate			2	%		2	%		2	%		2	%
	Expected dividend yield			0	%		1.2	%		0	%		1.2	%
	Expected volatility			42	%		44	%		42	%		44	%
	Expected term (in years)			5.9			5.6			5.9			5.6
	Risk-free rate
	The risk-free rate was based upon a treasury instrument whose term was consistent with the contractual term of the option.
	Expected dividend yield
	Generally, the current dividend yield is calculated by annualizing the cash dividend declared by the Company’s Board of Directors and dividing that result by the closing stock price on the grant date. However, in the fourth quarter of 2012, the Company paid the full annual dividends for 2013 and 2014 in advance, and therefore, the dividend yield for those years has been adjusted to zero. At the time of the 2013 valuation, a dividend yield of 1.04% was estimated for future periods from 2015 through the expected life of the option.
	Expected volatility
	The expected volatility was based upon a combination of historical volatility of the Company’s common stock over the contractual term of the option and implied volatility for traded options of the Company’s stock.
	Expected term
	The expected term was derived from the binomial lattice model from the impact of events that trigger exercises over time.
	The weighted-average grant-date fair values of stock options granted during the three-month periods ended September 29, 2013 and September 30, 2012 were $8.07 and $6.48, respectively. The weighted-average grant-date fair values of stock options granted during the nine-month periods ended September 29, 2013 and September 30, 2012 were $8.07 and $6.58, respectively.
	The Company stratifies its employee population into two groups: one consisting of senior management and another consisting of all other employees. The Company currently expects that approximately 71% of its stock options granted to senior management and 69% of its options granted to all other employees will actually vest. Therefore, the Company currently applies an estimated annual forfeiture rate of 12% to all unvested options for senior management and a rate of 13% for all other employees.
	The total stock-based compensation expense and the related income tax benefit recognized for the three-month period ended September 29, 2013 were $2,220,000 and $721,000, respectively, and for the three-month period ended September 30, 2012 were $1,492,000 and $478,000, respectively. The total stock-based compensation expense and the related income tax benefit recognized for the nine-month period ended September 29, 2013 were $8,299,000 and $2,725,000, respectively, and for the nine-month period ended September 30, 2012 were $6,795,000 and $2,212,000, respectively. No compensation expense was capitalized as of September 29, 2013 or December 31, 2012.
	The following table details the stock-based compensation expense by caption for each period presented on the Consolidated Statements of Operations (in thousands):
			Three-months Ended						Nine-months Ended
			September 29,			September 30,			September 29,			September 30,
			2013			2012			2013			2012
	Product cost of revenue		$	160		$	99		$	564		$	474
	Service cost of revenue			33			26			143			134
	Research, development, and engineering			546			385			2,009			1,735
	Selling, general, and administrative			1,481			982			5,583			4,452
			$	2,220		$	1,492		$	8,299		$	6,795
	The total intrinsic values of stock options exercised for the three-month periods ended September 29, 2013 and September 30, 2012 were $14,422,000 and $1,436,000, respectively. The total intrinsic values of stock options exercised for the nine-month periods ended September 29, 2013 and September 30, 2012 were $28,374,000 and $14,744,000, respectively. The total fair values of stock options vested for the three-month periods ended September 29, 2013 and September 30, 2012 were $197,000 and $242,000, respectively. The total fair values of stock options vested for the nine-month periods ended September 29, 2013 and September 30, 2012 were $9,428,000 and $8,927,000, respectively.
	As of September 29, 2013, total unrecognized compensation expense related to non-vested stock options was $10,411,000, which is expected to be recognized over a weighted-average period of 1.4 years.

Stock_Repurchase_Program

Stock Repurchase Program	9 Months Ended
	Sep. 29, 2013
Text Block [Abstract]
Stock Repurchase Program	NOTE 13: Stock Repurchase Program
	In April 2008, the Company’s Board of Directors authorized the repurchase of up to $50,000,000 of the Company’s common stock, primarily as a means to reduce the dilutive effect of employee stock options. As of September 29, 2013, the Company had repurchased 3,578,000 shares at a cost of $50,000,000 under this program, including 536,000 shares at a cost of $11,891,000 in the second quarter of 2013 and 291,000 shares at a cost of $8,109,000 in the third quarter of 2013. Stock repurchases under this program are now complete. In November 2011, the Company’s Board of Directors authorized the repurchase of up to $80,000,000 of the Company’s common stock to help reduce the dilutive effect of employee stock options. In the third quarter of 2013, the Company purchased 272,000 shares at a cost of $8,059,000 under this 2011 repurchase program. The Company may repurchase shares under the 2011 program in future periods depending upon a variety of factors, including, among other things, the impact of dilution from employee stock options, stock price, share availability, and cash requirements.

TwoforOne_Stock_Split

Two-for-One Stock Split	9 Months Ended
	Sep. 29, 2013
Equity [Abstract]
Two-for-One Stock Split	NOTE 14: Two-for-One Stock Split
	On July 29, 2013, the Company’s Board of Directors declared a two-for-one stock split, effected in the form of a stock dividend, on the shares of the Company’s common stock. Each shareholder of record on August 26, 2013, received an additional share of common stock for each share of common stock then held. The stock was distributed on September 16, 2013. The Company retained the current par value of $0.002 per share for all shares of common stock. All references in the financial statements to the number of shares outstanding, number of shares repurchased, per-share amounts, and stock option data related to the Company’s common stock have been restated to reflect the effect of the stock split for all periods presented.
	Stockholders’ equity reflects the stock split by reclassifying from “Additional paid in capital” to “Common stock” an amount equal to the par value of the additional shares arising from the split.

Taxes

Taxes	9 Months Ended
	Sep. 29, 2013
Income Tax Disclosure [Abstract]
Taxes	NOTE 15: Taxes
	A reconciliation of the United States federal statutory corporate tax rate to the Company’s effective tax rate, or income tax provision, was as follows:
		Three-months Ended						Nine-months Ended
		Sept. 29,			Sept. 30,			Sept. 29,			Sept. 30,
		2013			2012			2013			2012
	Income tax at federal statutory rate		35	%		35	%		35	%		35	%
	State income taxes, net of federal benefit		1			1			1			1
	Foreign tax rate differential		(17	)		(15	)		(17	)		(15	)
	Discrete events		(6	)		(2	)		(3	)		(1	)
	Income tax provision		13	%		19	%		16	%		20	%
	The effective tax rate for 2013 included the impact of the following discrete tax events: (1) a decrease in tax expense of $1,790,000 recorded in the third quarter from the expiration of statutes of limitations for certain reserves for income tax uncertainties, (2) an increase in tax expense of $267,000 recorded in the third quarter from the final true-up of the prior year’s tax accrual upon filing the actual tax returns, and (3) a decrease in tax expense of $555,000 recorded in the first quarter from the retroactive application of the 2012 research and development credit. The American Taxpayer Relief Act of 2012 was passed by Congress and signed into law on January 1, 2013. The provisions under this law are to be applied retroactively to January 1, 2012. As a result of the law being signed on January 1, 2013, the financial impact of the retroactive provision was recorded as a discrete event in the first quarter of 2013. These discrete tax events decreased the effective tax rate from a provision of 19% to a provision of 13% for the three-month period in 2013 and decreased the effective tax rate from a provision of 19% to a provision of 16% for the nine-month period in 2013.
	The effective tax rate for 2012 included the impact of the following discrete tax events: (1) a decrease in tax expense of $441,000 recorded in the third quarter from the expiration of statutes of limitations for certain reserves for income tax uncertainties and (2) an increase in tax expense of $84,000 recorded in the third quarter from the final true-up of the prior year’s tax accrual upon filing the actual tax returns. These discrete tax events decreased the effective tax rate from a provision of 21% to a provision of 19% for the three-month period in 2012 and decreased the effective tax rate from a provision of 21% to a provision of 20% for the nine-month period in 2012.
	During the nine-month period ended September 29, 2013, the Company recorded a $679,000 decrease in liabilities, net of deferred tax benefit, for uncertain tax positions that were recorded as income tax benefit, of which $1,597,000 of income tax benefit was recorded in the three-month period ended September 29, 2013. Estimated interest and penalties included in these amounts totaled $834,000 for the nine-month period ended September 29, 2013, of which $911,000 was recorded in the three-month period ended September 29, 2013.
	The Company’s reserve for income taxes, including gross interest and penalties, was $4,390,000 as of September 29, 2013, all of which was classified as noncurrent. The amount of gross interest and penalties included in these balances was $297,000. If the Company’s tax positions were sustained or the statutes of limitations related to certain positions expired, these reserves would be released and income tax expense would be reduced in a future period, less $361,000 that would be recorded through additional paid in capital. As a result of the expiration of certain statutes of limitations, there is a potential that a portion of these reserves could be released, which would decrease income tax expense by approximately $450,000 to $550,000 over the next twelve months.
	The Company has defined its major tax jurisdictions as the United States, Ireland, China, and Japan, and within the United States, Massachusetts and California. Within the United States, the tax years 2010 through 2012 remain open to examination by various taxing authorities, while the tax years 2009 through 2012 remain open to examination by various taxing authorities in other jurisdictions in which the Company operates. The Company has recently been notified by the Internal Revenue Service that its U.S. Federal tax returns for years 2010 and 2011 are under audit. The Company believes it is adequately reserved for these years.

WeightedAverage_Shares

Weighted-Average Shares	9 Months Ended
	Sep. 29, 2013
Earnings Per Share [Abstract]
Weighted-Average Shares	NOTE 16: Weighted-Average Shares
	On July 29, 2013 the Company’s Board of Directors declared a two-for-one stock split of the Company’s common stock, which was effected through a stock dividend distributed on September 16, 2013. All references made to share or per share amounts in the accompanying consolidated financial statements and applicable disclosures reflect this two-for-one stock split.
	Weighted-average shares were calculated as follows (in thousands):
		Three-months Ended				Nine-months Ended
		September 29,		September 30,		September 29,		September 30,
		2013		2012		2013		2012
	Basic weighted-average common shares outstanding		87,339		85,824		87,578		85,554
	Effect of dilutive stock options		2,020		1,434		1,872		1,666
	Weighted-average common and common-equivalent shares outstanding		89,359		87,258		89,450		87,220
	Stock options to purchase 76,653 and 1,357,004 shares of common stock, on a weighted-average basis, were outstanding during the three-month and nine-month periods ended September 29, 2013, respectively, and 1,870,684 and 1,784,698 for the same periods in 2012, but were not included in the calculation of dilutive net income per share because they were anti-dilutive.

Segment_Information

Segment Information	9 Months Ended
	Sep. 29, 2013
Segment Reporting [Abstract]
Segment Information	NOTE 17: Segment Information
	The Company has two reportable segments: the Modular Vision Systems Division (MVSD) and the Surface Inspection Systems Division (SISD). MVSD develops, manufactures, and markets modular vision systems that are used to control the manufacture of discrete items by locating, identifying, inspecting, and measuring them during the manufacturing process. SISD develops, manufactures, and markets surface inspection vision systems that are used to inspect surfaces of materials processed in a continuous fashion, such as metals, paper, nonwoven, plastics, and glass, to ensure there are no flaws or defects on the surfaces. Segments are determined based upon the way that management organizes its business for making operating decisions and assessing performance. The Company evaluates segment performance based upon income or loss from operations, excluding stock-based compensation expense.
	The following table summarizes information about the segments (in thousands):
	Three-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 29, 2013
	Product revenue	$	75,184	$	8,280	$	—		$	83,464
	Service revenue		2,758		4,566		—			7,324
	Operating income		26,038		2,916		(5,575	)		23,379
	Nine-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 29, 2013
	Product revenue	$	215,515	$	22,319	$	—		$	237,834
	Service revenue		7,151		13,205		—			20,356
	Operating income		71,641		6,875		(16,983	)		61,533
	Three-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 30, 2012
	Product revenue	$	64,971	$	7,466	$	—		$	72,437
	Service revenue		3,291		4,348		—			7,639
	Operating income		22,664		2,724		(3,585	)		21,803
	Nine-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 30, 2012
	Product revenue	$	198,935	$	23,358	$	—		$	222,293
	Service revenue		6,989		12,829		—			19,818
	Operating income		68,843		7,964		(13,913	)		62,894
	Reconciling items consist of stock-based compensation expense and unallocated corporate expenses, which primarily include corporate headquarters costs, professional fees, and patent infringement litigation. Additional asset information by segment is not produced internally for use by the chief operating decision maker, and therefore, is not presented. Additional asset information is not provided because cash and investments are commingled and the segments share assets and resources in a number of locations around the world.

New_Pronouncements_Policies

New Pronouncements (Policies)	9 Months Ended
	Sep. 29, 2013
Accounting Changes And Error Corrections [Abstract]
Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities	Accounting Standards Update (ASU) 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities”
	The amendments in ASU 2013-01 require companies to present enhanced disclosure about certain financial instruments and derivative instruments that are offset in the balance sheet or subject to an enforceable master netting arrangement or similar agreement. The disclosure requirement became effective, retrospectively, in the first quarter of our fiscal year ending December 31, 2013. However, as this ASU related only to presentation and disclosure it did not have an impact on our consolidated financial position, results of operations, or cash flows.
Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income	Accounting Standards Update (ASU) 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income”
	The amendments in ASU 2013-02 require companies to present information about amounts reclassified out of accumulated other comprehensive income (OCI) to net income, by component. The effect of significant reclassification adjustments being made out of accumulated OCI on the corresponding line items in net income must be presented when the item is reclassified in its entirety during one reporting period. While the new guidance in ASU 2013-12 changes the presentation of accumulated OCI, there are no changes to the components that are recognized in net income or OCI under current accounting guidance.
	Amounts reclassified from accumulated other comprehensive income to investment income on the Consolidated Statements of Operations were realized gains of $20,000 and $103,000 during the three-month and nine-month periods ended September 29, 2013, respectively, and realized gains of $340,000 and $1,411,000 during the three-month and nine-month periods ended September 30, 2012, respectively.
Presentation of Unrecognized Tax Benefit When Net Operating Loss Carryforward, Similar Tax Loss, or Tax Credit Carryforward Exists	Accounting Standards Update (ASU) 2013-11, “Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists”
	The amendments in ASU 2013-11 require companies to present an unrecognized tax benefit, or a portion thereof, as a reduction to a deferred tax asset for a net operating loss (NOL) carryforward or a similar tax loss or tax credit carryforward, unless the uncertain tax position is not available to reduce, or would not be used to reduce, the NOL or carryforward under the tax law in the same jurisdiction; otherwise, the unrecognized tax benefit should be presented as a gross liability and should not net the unrecognized tax benefit with a deferred tax asset. As the Company does not currently have any NOL carryforwards, this guidance will most likely apply to research and development tax credit carryforwards. ASU 2013-11 is effective for annual periods beginning after December 15, 2013 and should be applied to all unrecognized tax benefits that exist as of the effective date. Companies may choose to apply this guidance retrospectively to each prior reporting period presented. Management is the process of evaluating the impact of this Update.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 29, 2013
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table summarizes the financial assets and liabilities required to be measured at fair value on a recurring basis as of September 29, 2013 (in thousands):
		Quoted Prices in		Significant Other
		Active Markets		Observable
		for Identical		Inputs (Level 2)
		Assets (Level 1)
	Assets:
	Corporate stock	$	1,864	$	—
	Money market instruments		225		—
	Corporate bonds		—		210,341
	Asset-backed securities		—		69,928
	Treasury bills		—		69,277
	Sovereign bonds		—		29,923
	Municipal bonds		—		28,005
	Agency bonds		—		1,499
	Currency forward contracts		—		81
	Liabilities:
	Currency forward contracts		—		64

Cash_Cash_Equivalents_and_Inve1

Cash, Cash Equivalents, and Investments (Tables)	9 Months Ended
	Sep. 29, 2013
Cash And Cash Equivalents [Abstract]
Components of Cash, Cash Equivalents, and Investments	Cash, cash equivalents, and investments consisted of the following (in thousands):
		September 29,		December 31,
		2013		2012
	Cash	$	30,221	$	34,986
	Cash equivalents		—		5,098
	Money market instruments		225		5,076
	Cash and cash equivalents		30,446		45,160
	Corporate bonds		104,720		46,001
	Asset-backed securities		41,269		17,666
	Municipal bonds		17,013		16,224
	Treasury bills		11,654		5,997
	Sovereign bonds		8,553		3,986
	Corporate stock		1,864		2,131
	Agency bonds		1,499		7,482
	Covered bonds		—		5,618
	Short-term investments		186,572		105,105
	Corporate bonds		105,621		100,072
	Treasury bills		57,623		36,276
	Asset-backed securities		28,659		34,710
	Sovereign bonds		21,370		10,606
	Municipal bonds		10,992		17,846
	Agency bonds		—		29,441
	Covered bonds		—		5,564
	Limited partnership interest (accounted for using cost method)		2,455		3,740
	Long-term investments		226,720		238,255
		$	443,738	$	388,520
Summary of Available-for-Sale Investments	The following tables summarize the Company’s available-for-sale investments as of September 29, 2013 (in thousands):
		Amortized		Gross			Gross			Fair Value
		Cost		Unrealized			Unrealized
				Gains			Losses
	Short-term:
	Corporate bonds	$	104,580	$	270		$	(130	)	$	104,720
	Asset-backed securities		41,600		7			(338	)		41,269
	Municipal bonds		16,969		44			—			17,013
	Treasury bills		11,647		7			—			11,654
	Sovereign bonds		8,554		9			(10	)		8,553
	Agency bonds		1,500		—			(1	)		1,499
	Long-term:
	Corporate bonds		105,251		513			(143	)		105,621
	Treasury bills		57,604		24			(5	)		57,623
	Asset-backed securities		28,810		10			(161	)		28,659
	Sovereign bonds		21,386		57			(73	)		21,370
	Municipal bonds		10,957		45			(10	)		10,992
		$	408,858	$	986		$	(871	)	$	408,973
Gross Unrealized Losses and Fair Values for Available-for-Sale Investments
		Unrealized Loss Position For:
		Less than 12 Months					12 Months or Greater						Total
		Fair Value		Unrealized			Fair Value			Unrealized			Fair Value		Unrealized
				Losses						Losses					Losses
	Corporate bonds	$	62,910	$	(272	)	$	2,455		$	(1	)	$	65,365	$	(273	)
	Asset- backed securities		41,848		(102	)		16,332			(397	)		58,180		(499	)
	Sovereign bonds		9,300		(25	)		888			(58	)		10,188		(83	)
	Treasury bills		7,614		(5	)		—			—			7,614		(5	)
	Municipal bonds		4,374		(10	)		—			—			4,374		(10	)
	Agency bonds		1,499		(1	)		—			—			1,499		(1	)
		$	127,545	$	(415	)	$	19,675		$	(456	)	$	147,220	$	(871	)
Effective Maturity Dates of Available-for-Sale Investments	The following table presents the effective maturity dates of the Company’s available-for-sale investments as of September 29, 2013 (in thousands):
		<1		2-Jan			3-Feb			4-Mar			5-Apr		Total
		Year		Years			Years			Years			Years
	Corporate bonds	$	104,720	$	61,596		$	41,299		$	2,203		$	523	$	210,341
	Asset-backed securities		41,269		28,659			—			—			—		69,928
	Treasury bills		11,654		48,015			9,608			—			—		69,277
	Sovereign bonds		8,553		9,571			10,911			—			888		29,923
	Municipal bonds		17,013		4,576			4,531			1,385			500		28,005
	Agency bonds		1,499		—			—			—			—		1,499
		$	184,708	$	152,417		$	66,349		$	3,588		$	1,911	$	408,973

Inventories_Tables

Inventories (Tables)	9 Months Ended
	Sep. 29, 2013
Inventory Disclosure [Abstract]
Inventories	Inventories consisted of the following (in thousands):
		September 29,		December 31,
		2013		2012
	Raw materials	$	14,050	$	12,667
	Work-in-process		3,935		4,193
	Finished goods		9,640		9,322
		$	27,625	$	26,182

Warranty_Obligations_Tables

Warranty Obligations (Tables)	9 Months Ended
	Sep. 29, 2013
Guarantees [Abstract]
Changes in Warranty Obligations	The changes in the warranty obligations were as follows (in thousands):
	Balance as of December 31, 2012	$	2,256
	Provisions for warranties issued during the period		2,027
	Fulfillment of warranty obligations		(1,535	)
	Foreign exchange rate changes		64
	Balance as of September 29, 2013	$	2,812

Guarantees_Tables

Guarantees (Tables)	9 Months Ended
	Sep. 29, 2013
Guarantees [Abstract]
Details of Letters of Credit Outstanding	The following table details the letters of credit outstanding as of September 29, 2013:
	Type	Guarantee		Guarantee due date
		Amount
		(in thousands)
	Bank Guarantees	$	294	Various from October 2013 to November 2013
	Performance Bonds		159	Various from January 2015 to March 2016
	Warranty Bonds		1,095	Various from October 2013 to August 2015
		$	1,548

Derivative_Instruments_Tables

Derivative Instruments (Tables)	9 Months Ended
	Sep. 29, 2013
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Outstanding Forward Contracts	As of September 29, 2013, the Company had the following outstanding forward contracts that were entered into to mitigate foreign currency exchange rate risk (in thousands):
	Currency	Notional				USD
		Value				Equivalent
	Chinese Renminbi		20,000			$	3,213
	Japanese Yen		235,400				2,395
	Singapore Dollar		3,025				2,379
	Euro		1,035				1,400
	British Pound		650				1,036
	Korean Won		1,121,500				1,029
	Taiwanese Dollar		28,450				952
	Swedish Krona		5,800				891
	Hungarian Forint		135,000				603
Information Regarding Fair Value of Forward Contracts Outstanding	Information regarding the fair value of the forward contracts outstanding as of September 29, 2013 and December 31, 2012 was as follows (in thousands):
		Asset Derivatives									Liability Derivatives
		Balance		Fair Value							Balance	Fair Value
		Sheet		September 29,				December 31,			Sheet	September 29,		December 31,
		Location		2013				2012			Location	2013		2012
	Currency forward contracts	Prepaid expenses and		$	81			$	44		Accrued	$	64	$	14
		other current assets									expenses
Information Regarding Effect of Forward Contracts, Net of Underlying Exposure, on Consolidated Statements of Operations	Information regarding the effect of the forward contracts, net of the underlying exposure, on the Consolidated Statements of Operations for the three-month and nine-month periods ended September 29, 2013 and September 30, 2012 was as follows (in thousands):
				Amount of Loss Recognized								Amount of Gain (Loss)
												Recognized
		Location of		Three-months ended							Location of	Nine-months ended
		Loss		September 29,				September 30,			Gain (Loss)	September 29,		September 30,
		Recognized		2013				2012			Recognized	2013		2012
	Currency forward contracts	Foreign currency		$	(186	)		$	(546	)	Foreign currency	$	10	$	(637	)
		loss									gain (loss)

StockBased_Compensation_Expens1

Stock-Based Compensation Expense (Tables)	9 Months Ended
	Sep. 29, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	The following table summarizes the Company’s stock option activity for the nine-month period ended September 29, 2013:
			Shares			Weighted-			Weighted-			Aggregate
			(in thousands)			Average			Average			Intrinsic
						Exercise			Remaining			Value
						Price			Contractual			(in thousands)
									Term (in years)
	Outstanding as of December 31, 2012			7,118		$	12.78
	Granted			1,711			21.29
	Exercised			(2,275	)		11.42
	Forfeited or expired			(259	)		16.29
	Outstanding as of September 29, 2013			6,295		$	15.44			7.4		$	100,525
	Exercisable as of September 29, 2013			1,806		$	11.55			5.4		$	35,855
	Options vested or expected to vest at September 29, 2013 (1)			5,577		$	15.09			7.2		$	91,041
	-1	In addition to the vested options, the Company expects a portion of the unvested options to vest at some point in the future. Options expected to vest are calculated by applying an estimated forfeiture rate to the unvested options.
Weighted-Average Assumptions Used in Estimating Fair Values of Stock Options Granted	The fair values of stock options granted in each period presented were estimated using the following weighted-average assumptions:
			Three-months Ended						Nine-months Ended
			September 29,			September 30,			September 29,			September 30,
			2013			2012			2013			2012
	Risk-free rate			2	%		2	%		2	%		2	%
	Expected dividend yield			0	%		1.2	%		0	%		1.2	%
	Expected volatility			42	%		44	%		42	%		44	%
	Expected term (in years)			5.9			5.6			5.9			5.6
Stock-Based Compensation Expense	The following table details the stock-based compensation expense by caption for each period presented on the Consolidated Statements of Operations (in thousands):
			Three-months Ended						Nine-months Ended
			September 29,			September 30,			September 29,			September 30,
			2013			2012			2013			2012
	Product cost of revenue		$	160		$	99		$	564		$	474
	Service cost of revenue			33			26			143			134
	Research, development, and engineering			546			385			2,009			1,735
	Selling, general, and administrative			1,481			982			5,583			4,452
			$	2,220		$	1,492		$	8,299		$	6,795

Taxes_Tables

Taxes (Tables)	9 Months Ended
	Sep. 29, 2013
Income Tax Disclosure [Abstract]
Reconciliation of United States Federal Statutory Corporate Tax Rate to Company's Effective Tax Rate, or Income Tax Provision	A reconciliation of the United States federal statutory corporate tax rate to the Company’s effective tax rate, or income tax provision, was as follows:
		Three-months Ended						Nine-months Ended
		Sept. 29,			Sept. 30,			Sept. 29,			Sept. 30,
		2013			2012			2013			2012
	Income tax at federal statutory rate		35	%		35	%		35	%		35	%
	State income taxes, net of federal benefit		1			1			1			1
	Foreign tax rate differential		(17	)		(15	)		(17	)		(15	)
	Discrete events		(6	)		(2	)		(3	)		(1	)
	Income tax provision		13	%		19	%		16	%		20	%

WeightedAverage_Shares_Tables

Weighted-Average Shares (Tables)	9 Months Ended
	Sep. 29, 2013
Earnings Per Share [Abstract]
Calculation of Weighted-Average Shares	Weighted-average shares were calculated as follows (in thousands):
		Three-months Ended				Nine-months Ended
		September 29,		September 30,		September 29,		September 30,
		2013		2012		2013		2012
	Basic weighted-average common shares outstanding		87,339		85,824		87,578		85,554
	Effect of dilutive stock options		2,020		1,434		1,872		1,666
	Weighted-average common and common-equivalent shares outstanding		89,359		87,258		89,450		87,220

Segment_Information_Tables

Segment Information (Tables)	9 Months Ended
	Sep. 29, 2013
Segment Reporting [Abstract]
Information About Segments	The following table summarizes information about the segments (in thousands):
	Three-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 29, 2013
	Product revenue	$	75,184	$	8,280	$	—		$	83,464
	Service revenue		2,758		4,566		—			7,324
	Operating income		26,038		2,916		(5,575	)		23,379
	Nine-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 29, 2013
	Product revenue	$	215,515	$	22,319	$	—		$	237,834
	Service revenue		7,151		13,205		—			20,356
	Operating income		71,641		6,875		(16,983	)		61,533
	Three-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 30, 2012
	Product revenue	$	64,971	$	7,466	$	—		$	72,437
	Service revenue		3,291		4,348		—			7,639
	Operating income		22,664		2,724		(3,585	)		21,803
	Nine-months Ended	MVSD		SISD		Reconciling Items			Consolidated
	September 30, 2012
	Product revenue	$	198,935	$	23,358	$	—		$	222,293
	Service revenue		6,989		12,829		—			19,818
	Operating income		68,843		7,964		(13,913	)		62,894

Summary_of_Significant_Account1

Summary of Significant Accounting Policies - Additional Information (Detail)	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 29, 2013	Sep. 29, 2013	Sep. 29, 2013
Accounting Policies [Abstract]
Stock split conversion ratio	2	2	2

New_Pronouncements_Additional_

New Pronouncements - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
New Accounting Pronouncement Or Change In Accounting Principle Retrospective Adjustments [Abstract]
Reclassification from accumulated other comprehensive income to investment income	$20,000	$340,000	$103,000	$1,411,000

Fair_Value_Measurements_Assets

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (USD $)	Sep. 29, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets:
Money market instruments	$225	$5,076
Financial assets at fair value	408,973
Corporate Bonds [Member]
Assets:
Financial assets at fair value	210,341
Asset-Backed Securities [Member]
Assets:
Financial assets at fair value	69,928
Treasury Bills [Member]
Assets:
Financial assets at fair value	69,277
Sovereign Bonds [Member]
Assets:
Financial assets at fair value	29,923
Municipal Bonds [Member]
Assets:
Financial assets at fair value	28,005
Agency Bonds [Member]
Assets:
Financial assets at fair value	1,499
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Assets:
Corporate stock	1,864
Money market instruments	225
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Corporate Bonds [Member]
Assets:
Financial assets at fair value	210,341
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Asset-Backed Securities [Member]
Assets:
Financial assets at fair value	69,928
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Treasury Bills [Member]
Assets:
Financial assets at fair value	69,277
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Sovereign Bonds [Member]
Assets:
Financial assets at fair value	29,923
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Municipal Bonds [Member]
Assets:
Financial assets at fair value	28,005
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Agency Bonds [Member]
Assets:
Financial assets at fair value	1,499
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member] | Currency Forward Contracts [Member]
Assets:
Currency forward contracts	81
Liabilities:
Currency forward contracts	$64

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 29, 2013
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other-than-temporary impairment loss	$0
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other-than-temporary impairment loss	0
Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other-than-temporary impairment loss	$0

Cash_Cash_Equivalents_and_Inve2

Cash, Cash Equivalents, and Investments - Components of Cash, Cash Equivalents, and Investments (Detail) (USD $)	Sep. 29, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Cash	$30,221	$34,986
Cash equivalents		5,098
Money market instruments	225	5,076
Cash and cash equivalents	30,446	45,160	54,158	38,103
Short-term investments	186,572	105,105
Limited partnership interest (accounted for using cost method)	2,455	3,740
Long-term investments	226,720	238,255
Total	443,738	388,520
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	104,720	46,001
Long-term investments	105,621	100,072
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	41,269	17,666
Long-term investments	28,659	34,710
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	17,013	16,224
Long-term investments	10,992	17,846
Treasury Bills [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	11,654	5,997
Long-term investments	57,623	36,276
Sovereign Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	8,553	3,986
Long-term investments	21,370	10,606
Corporate Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	1,864	2,131
Agency Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	1,499	7,482
Long-term investments		29,441
Covered Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments		5,618
Long-term investments		$5,564

Cash_Cash_Equivalents_and_Inve3

Cash, Cash Equivalents, and Investments - Summary of Available-for-Sale Investments (Detail) (USD $)	Sep. 29, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$408,858
Gross Unrealized Gains	986
Gross Unrealized Losses	-871
Fair Value	408,973
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	210,341
Corporate Bonds [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	104,580
Gross Unrealized Gains	270
Gross Unrealized Losses	-130
Fair Value	104,720
Corporate Bonds [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	105,251
Gross Unrealized Gains	513
Gross Unrealized Losses	-143
Fair Value	105,621
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	69,928
Asset-Backed Securities [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	41,600
Gross Unrealized Gains	7
Gross Unrealized Losses	-338
Fair Value	41,269
Asset-Backed Securities [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	28,810
Gross Unrealized Gains	10
Gross Unrealized Losses	-161
Fair Value	28,659
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	28,005
Municipal Bonds [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,969
Gross Unrealized Gains	44
Fair Value	17,013
Municipal Bonds [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,957
Gross Unrealized Gains	45
Gross Unrealized Losses	-10
Fair Value	10,992
Treasury Bills [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	69,277
Treasury Bills [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,647
Gross Unrealized Gains	7
Fair Value	11,654
Treasury Bills [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	57,604
Gross Unrealized Gains	24
Gross Unrealized Losses	-5
Fair Value	57,623
Sovereign Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	29,923
Sovereign Bonds [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,554
Gross Unrealized Gains	9
Gross Unrealized Losses	-10
Fair Value	8,553
Sovereign Bonds [Member] | Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,386
Gross Unrealized Gains	57
Gross Unrealized Losses	-73
Fair Value	21,370
Agency Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	1,499
Agency Bonds [Member] | Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,500
Gross Unrealized Losses	-1
Fair Value	$1,499

Cash_Cash_Equivalents_and_Inve4

Cash, Cash Equivalents, and Investments - Gross Unrealized Losses and Fair Values for Available-for-Sale Investments (Detail) (USD $)	Sep. 29, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	$127,545
Unrealized Losses, Less than 12 Months	-415
Fair Value, 12 Months or Greater	19,675
Unrealized Losses, 12 Months or Greater	-456
Total Fair Value	147,220
Total Unrealized Losses	-871
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	62,910
Unrealized Losses, Less than 12 Months	-272
Fair Value, 12 Months or Greater	2,455
Unrealized Losses, 12 Months or Greater	-1
Total Fair Value	65,365
Total Unrealized Losses	-273
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	41,848
Unrealized Losses, Less than 12 Months	-102
Fair Value, 12 Months or Greater	16,332
Unrealized Losses, 12 Months or Greater	-397
Total Fair Value	58,180
Total Unrealized Losses	-499
Sovereign Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	9,300
Unrealized Losses, Less than 12 Months	-25
Fair Value, 12 Months or Greater	888
Unrealized Losses, 12 Months or Greater	-58
Total Fair Value	10,188
Total Unrealized Losses	-83
Treasury Bills [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	7,614
Unrealized Losses, Less than 12 Months	-5
Total Fair Value	7,614
Total Unrealized Losses	-5
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	4,374
Unrealized Losses, Less than 12 Months	-10
Total Fair Value	4,374
Total Unrealized Losses	-10
Agency Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	1,499
Unrealized Losses, Less than 12 Months	-1
Total Fair Value	1,499
Total Unrealized Losses	($1)

Cash_Cash_Equivalents_and_Inve5

Cash, Cash Equivalents, and Investments - Additional Information (Detail) (USD $)	3 Months Ended			9 Months Ended
	Sep. 29, 2013	Jun. 30, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Dec. 31, 2012
						Equity Securities [Member]	Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross realized gains on sale of investments	$32,000		$342,000	$182,000	$1,669,000
Gross realized losses on sale of investments	12,000		1,000	79,000	239,000
Fair value						1,864,000	2,131,000
Net unrealized loss				267,000		267,000
Maximum amount committed to invest in limited partnership				20,500,000
Contribution to limited partnership	19,886,000			19,886,000
Remaining amount of commitment in limited partnership	614,000			614,000
Investment expiration date				31-Dec-13
Number of contributions made during the period				0
Cash distribution received		$1,285,000

Cash_Cash_Equivalents_and_Inve6

Cash, Cash Equivalents, and Investments - Effective Maturity Dates of Available-for-Sale Investments (Detail) (USD $)	Sep. 29, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	$184,708
1-2 Years	152,417
2-3 Years	66,349
3-4 Years	3,588
4-5 Years	1,911
Fair Value	408,973
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	104,720
1-2 Years	61,596
2-3 Years	41,299
3-4 Years	2,203
4-5 Years	523
Fair Value	210,341
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	41,269
1-2 Years	28,659
Fair Value	69,928
Treasury Bills [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	11,654
1-2 Years	48,015
2-3 Years	9,608
Fair Value	69,277
Sovereign Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	8,553
1-2 Years	9,571
2-3 Years	10,911
4-5 Years	888
Fair Value	29,923
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	17,013
1-2 Years	4,576
2-3 Years	4,531
3-4 Years	1,385
4-5 Years	500
Fair Value	28,005
Agency Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 1 Year	1,499
Fair Value	$1,499

Inventories_Inventories_Detail

Inventories - Inventories (Detail) (USD $)	Sep. 29, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]
Raw materials	$14,050	$12,667
Work-in-process	3,935	4,193
Finished goods	9,640	9,322
Inventories	$27,625	$26,182

Warranty_Obligations_Changes_i

Warranty Obligations - Changes in Warranty Obligations (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013
Payables And Accruals [Abstract]
Beginning Balance	$2,256
Provisions for warranties issued during the period	2,027
Fulfillment of warranty obligations	-1,535
Foreign exchange rate changes	64
Ending Balance	$2,812

Contingencies_Additional_Infor

Contingencies - Additional Information (Detail)	1 Months Ended
	Jul. 31, 2010	Dec. 31, 2009	Sep. 30, 2009
	Patents	Respondent	Respondent
Leases [Abstract]
Number of respondents with whom a settlement was reached		5	2
Number of the company's patents found invalid	2

Guarantees_Additional_Informat

Guarantees - Additional Information (Detail)	9 Months Ended
	Sep. 29, 2013
	Category
Guarantees [Abstract]
Number of categories of letters of credit	3

Guarantees_Details_of_Letters_

Guarantees - Details of Letters of Credit Outstanding (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013
Guarantor Obligations [Line Items]
Guarantee Amount	$1,548
Bank Guarantees [Member]
Guarantor Obligations [Line Items]
Guarantee Amount	294
Guarantee due date	Various from October 2013 to November 2013
Performance Bonds [Member]
Guarantor Obligations [Line Items]
Guarantee Amount	159
Guarantee due date	Various from January 2015 to March 2016
Warranty Bonds [Member]
Guarantor Obligations [Line Items]
Guarantee Amount	$1,095
Guarantee due date	Various from October 2013 to August 2015

Derivative_Instruments_Additio

Derivative Instruments - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative instruments maturity period			3 months
Net foreign currency gains (losses)	($442)	($409)	($303)	($1,077)

Derivative_Instruments_Outstan

Derivative Instruments - Outstanding Forward Contracts (Detail) (Currency Forward Contracts [Member])

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

Sep. 29, 2013

In Thousands, unless otherwise specified

Chinese Renminbi [Member]

Chinese Renminbi [Member]

Japanese Yen [Member]

Japanese Yen [Member]

Singapore Dollar [Member]

Singapore Dollar [Member]

Euro [Member]

Euro [Member]

British Pound [Member]

British Pound [Member]

Korean Won [Member]

Korean Won [Member]

Taiwanese Dollar [Member]

Taiwanese Dollar [Member]

Swedish Krona [Member]

Swedish Krona [Member]

Hungarian Forint [Member]

Hungarian Forint [Member]

USD ($)

CNY

USD ($)

JPY (¥)

USD ($)

SGD

USD ($)

EUR (€)

USD ($)

GBP (£)

USD ($)

KRW

USD ($)

TWD

USD ($)

SEK

USD ($)

HUF

Derivative [Line Items]

Outstanding forward contracts

$3,213

20,000

$2,395

¥ 235,400

$2,379

3,025

$1,400

€ 1,035

$1,036

£ 650

$1,029

1,121,500

$952

28,450

$891

5,800

$603

135,000

Derivative_Instruments_Informa

Derivative Instruments - Information Regarding Fair Value of Forward Contracts Outstanding (Detail) (Currency Forward Contracts [Member], USD $)	Sep. 29, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$81	$44
Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	$64	$14

Derivative_Instruments_Informa1

Derivative Instruments - Information Regarding Effect of Forward Contracts, Net of Underlying Exposure, on Consolidated Statements of Operations (Detail) (Foreign Currency Gain (Loss) [Member], Currency Forward Contracts [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Foreign Currency Gain (Loss) [Member] | Currency Forward Contracts [Member]
Information regarding the effect of the forward contracts, net of the underlying exposure, on the Consolidated Statements of Operations
Amount of Gain (Loss) Recognized	($186)	($546)	$10	($637)

StockBased_Compensation_Expens2

Stock-Based Compensation Expense - Additional Information (Detail) (USD $)	3 Months Ended			9 Months Ended
	Sep. 29, 2013	Dec. 31, 2012	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
	OptionPlan			OptionPlan
	Employees			Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under stock option plans	11,178,930			11,178,930
Number of stock option plans	2			2
Expected dividend yield	0.00%	0.00%	1.20%	0.00%	1.20%
Weighted-average grant-date fair values of stock options granted	$8.07		$6.48	$8.07	$6.58
Number of groups within the employee population	2			2
Percentage of stock options granted to senior management expected to vest	71.00%			71.00%
Percentage of stock options granted to all other employees expected to vest	69.00%			69.00%
Estimated forfeiture rate for unvested options for senior management	12.00%			12.00%
Estimated forfeiture rate for unvested options for all non-senior management	13.00%			13.00%
Stock-based compensation expense	$2,220,000		$1,492,000	$8,299,000	$6,795,000
Income tax benefit recognized related to stock-based compensation expense	721,000		478,000	2,725,000	2,212,000
Compensation expense was capitalized	0	0		0
Total intrinsic values of stock options exercised	14,422,000		1,436,000	28,374,000	14,744,000
Total fair values of stock options vest	197,000		242,000	9,428,000	8,927,000
Total unrecognized compensation expense related to non-vested stock options	$10,411,000			$10,411,000
Weighted-average period for unrecognized compensation expense related to non-vested stock options (years)				1 year 4 months 24 days
General Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under stock option plans	8,660,710			8,660,710
Expiration period of stock option plan				10 years
Vesting period for stock option plans				4 years
Stock Option and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under stock option plans	2,518,220			2,518,220
Expiration period of stock option plan				10 years
Vesting period for stock option plans				4 years
2015 Through Expected Life of Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield				1.04%

StockBased_Compensation_Expens3

Stock-Based Compensation Expense - Summary of Stock Option Activity (Detail) (USD $)	9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 29, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding, Shares	7,118
Granted, Shares	1,711
Exercised, Shares	-2,275
Forfeited or expired, Shares	-259
Outstanding, Shares	6,295
Exercisable, Shares	1,806
Options vested or expected to vest, Shares	5,577
Outstanding, Weighted-Average Exercise Price	$12.78
Granted, Weighted-Average Exercise Price	$21.29
Exercised, Weighted-Average Exercise Price	$11.42
Forfeited or expired, Weighted-Average Exercise Price	$16.29
Outstanding, Weighted-Average Exercise Price	$15.44
Exercisable, Weighted-Average Exercise Price	$11.55
Options vested or expected to vest, Weighted-Average Exercise Price	$15.09
Outstanding, Weighted-Average Remaining Contractual Term (in years)	7 years 4 months 24 days
Exercisable, Weighted-Average Remaining Contractual Term (in years)	5 years 4 months 24 days
Options vested or expected to vest, Weighted-Average Remaining Contractual Term (in years)	7 years 2 months 12 days
Outstanding, Aggregate Intrinsic Value	$100,525
Exercisable, Aggregate Intrinsic Value	35,855
Options vested or expected to vest, Aggregate Intrinsic Value	$91,041

StockBased_Compensation_Expens4

Stock-Based Compensation Expense - Weighted-Average Assumptions Used in Estimating Fair Values of Stock Options Granted (Detail)	3 Months Ended			9 Months Ended
	Sep. 29, 2013	Dec. 31, 2012	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Risk-free rate	2.00%		2.00%	2.00%	2.00%
Expected dividend yield	0.00%	0.00%	1.20%	0.00%	1.20%
Expected volatility	42.00%		44.00%	42.00%	44.00%
Expected term (in years)	5 years 10 months 24 days		5 years 7 months 6 days	5 years 10 months 24 days	5 years 7 months 6 days

StockBased_Compensation_Expens5

Stock-Based Compensation Expense - Stock-Based Compensation Expense (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$2,220	$1,492	$8,299	$6,795
Product Cost of Revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	160	99	564	474
Service Cost of Revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	33	26	143	134
Research, Development, and Engineering [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	546	385	2,009	1,735
Selling, General, and Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$1,481	$982	$5,583	$4,452

Stock_Repurchase_Program_Addit

Stock Repurchase Program - Additional Information (Detail) (USD $)	1 Months Ended		3 Months Ended		9 Months Ended
	Nov. 01, 2011	Apr. 01, 2008	Sep. 29, 2013	Jun. 30, 2013	Sep. 29, 2013
Equity [Line Items]
Repurchase of authorized common stock	$80,000,000	$50,000,000
Repurchase of shares			3,578,000		3,578,000
Repurchase of shares during period			291,000	536,000
Repurchase of shares, value			50,000,000		50,000,000
Repurchase of shares during period, value			8,109,000	11,891,000	28,059,000
2011 Stock Repurchase Program [Member]
Equity [Line Items]
Repurchase of shares during period			272,000
Repurchase of shares during period, value			$8,059,000

TwoforOne_Stock_Split_Addition

Two-for-One Stock Split - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 29, 2013	Sep. 29, 2013	Sep. 29, 2013	Dec. 31, 2012
Equity [Abstract]
Common stock, par or stated value per share		$0.00	$0.00	$0.00
Stock split conversion ratio	2	2	2

Taxes_Reconciliation_of_United

Taxes - Reconciliation of United States Federal Statutory Corporate Tax Rate to Company's Effective Tax Rate, or Income Tax Provision (Detail)	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Income tax at federal statutory rate	35.00%	35.00%	35.00%	35.00%
State income taxes, net of federal benefit	1.00%	1.00%	1.00%	1.00%
Foreign tax rate differential	-17.00%	-15.00%	-17.00%	-15.00%
Discrete events	-6.00%	-2.00%	-3.00%	-1.00%
Income tax provision	13.00%	19.00%	16.00%	20.00%

Taxes_Additional_Information_D

Taxes - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012	Dec. 31, 2012	Mar. 31, 2013
						Research and Development Tax Credit [Member]
Tax Credit Carryforward [Line Items]
Increase (decrease) in tax expense upon the expiration of the statutes of limitation for certain reserves for income tax uncertainties	($1,790,000)	($441,000)
Increase (decrease) in tax expense for the final true-up of the prior year's tax accrual upon filing the actual tax returns	267,000	84,000
Reduction in tax expense						555,000
Effective discrete tax rate	19.00%	21.00%	19.00%	21.00%
Provision for effective tax rate	13.00%	19.00%	16.00%	20.00%
Increase (decrease) in liabilities, net of deferred tax benefit, for uncertain tax positions			-679,000
Income tax expense benefit on uncertain tax position	1,597,000
Increase (decrease) in interest and penalties	911,000		834,000
Reserve for income taxes, total	4,390,000		4,390,000		5,216,000
Interest and penalties, gross	297,000		297,000
Reserve for income taxes to be recorded in additional paid in capital			361,000
Minimum decrease in income tax expense due to release in reserves			450,000
Maximum decrease in income tax expense due to release in reserves			$550,000
Tax years open to examination by various taxing authorities			2010 through 2012
Tax years open to examination by various taxing authorities for other entities			2009 through 2012
Tax years currently under audit by internal revenue service for U.S. federal returns			2010 and 2011

WeightedAverage_Shares_Additio

Weighted-Average Shares - Additional Information (Detail)	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 29, 2013	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Stock split conversion ratio	2	2		2
Stock options to purchase anti-dilutive common stock		76,653	1,870,684	1,357,004	1,784,698

WeightedAverage_Shares_Calcula

Weighted-Average Shares - Calculation of Weighted-Average Shares (Detail)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013		Sep. 30, 2012		Sep. 29, 2013		Sep. 30, 2012
Earnings Per Share [Abstract]
Basic weighted-average common shares outstanding	87,339	[1]	85,824	[1]	87,578	[1]	85,554	[1]
Effect of dilutive stock options	2,020		1,434		1,872		1,666
Weighted-average common and common-equivalent shares outstanding	89,359	[1]	87,258	[1]	89,450	[1]	87,220	[1]
[1]	Prior period results have been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend which occurred in September 2013.

Segment_Information_Additional

Segment Information - Additional Information (Detail)	9 Months Ended
	Sep. 29, 2013
	Segment
Segment Reporting [Abstract]
Number of reportable segments	2

Segment_Information_Informatio

Segment Information - Information About Segments (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Product revenue	$83,464	$72,437	$237,834	$222,293
Service revenue	7,324	7,639	20,356	19,818
Operating income	23,379	21,803	61,533	62,894
Operating Segments [Member] | MVSD [Member]
Segment Reporting Information [Line Items]
Product revenue	75,184	64,971	215,515	198,935
Service revenue	2,758	3,291	7,151	6,989
Operating income	26,038	22,664	71,641	68,843
Operating Segments [Member] | SISD [Member]
Segment Reporting Information [Line Items]
Product revenue	8,280	7,466	22,319	23,358
Service revenue	4,566	4,348	13,205	12,829
Operating income	2,916	2,724	6,875	7,964
Reconciling Items [Member]
Segment Reporting Information [Line Items]
Operating income	($5,575)	($3,585)	($16,983)	($13,913)