Stock-Based Compensation Expense (Tables)

6 Months Ended

Jul. 01, 2012

Stock-Based Compensation Expense [Abstract]

Summary of stock option activity

	Shares (in  thousands)			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding as of December 31, 2011		4,473		$	24.48
Granted		17			41.40
Exercised		(654	)		21.33
Forfeited or expired		(81	)		24.89
Outstanding as of July 1, 2012		3,755		$	25.15		7.5	$	26,464
Exercisable as of July 1, 2012		1,347		$	20.90		5.8	$	14,648

Weighted-average assumptions used in estimating the fair values of stock options granted

	Three-months Ended						Six-months Ended
	July 1, 2012			July 3, 2011			July 1, 2012			July 3, 2011
Risk-free rate		2.0	%		3.6	%		2.0	%		3.6	%
Expected dividend yield		1.2	%		1.0	%		1.2	%		1.0	%
Expected volatility		44	%		42	%		44	%		42	%
Expected term (in years)		5.7			5.2			5.7			5.4

Stock-based compensation expense

	Three-months Ended				Six-months Ended
	July 1, 2012		July 3, 2011		July 1, 2012		July 3, 2011
Product cost of revenue	$	135	$	105	$	375	$	270
Service cost of revenue		40		39		108		109
Research, development, and engineering		483		529		1,350		1,338
Selling, general, and administrative		1,331		1,284		3,470		2,592
	$	1,989	$	1,957	$	5,303	$	4,309