Stock Plans (Tables)

3 Months Ended

Mar. 30, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Total Compensation Recognized Related to Outstanding Equity Awards

The following table summarizes total pre-tax compensation expense recognized related to the Company’s stock options, restricted stock, restricted stock units, performance units and stock grants, net of estimated forfeitures, included in the Company’s condensed consolidated statements of operations for the three months ended March 30, 2014 and March 31, 2013:

	Three Months Ended
	March 30, 2014		March 31, 2013
	(In thousands)
Cost of product and service revenue	$	333	$	313
Research and development expenses	141		216
Selling, general and administrative expenses	4,042		3,887
Total stock-based compensation expense	$	4,516	$	4,416

Weighted-Average Assumptions Used in the Black-Scholes Option Pricing Model

The Company’s weighted-average assumptions used in the Black-Scholes option pricing model were as follows:

	Three Months Ended
	March 30, 2014		March 31, 2013
Risk-free interest rate	1.5	%	0.9	%
Expected dividend yield	0.7	%	0.8	%
Expected lives	5 years		5 years
Expected stock volatility	30.9	%	38.5	%

Summary of Stock Option Activity

The following table summarizes stock option activity for the three months ended March 30, 2014:

	Number of Shares		Weighted- Average Price		Weighted-Average Remaining Contractual Term	Total Intrinsic Value
	(In thousands)				(In years)	(In millions)
Outstanding at December 29, 2013	3,494		$	23.34
Granted	446		43.08
Exercised	(310	)	23.30
Canceled	(4	)	20.97
Forfeited	(16	)	29.58
Outstanding at March 30, 2014	3,610		$	25.75	3.8	$	65.1
Exercisable at March 30, 2014	2,567		$	21.83	2.9	$	56.4
Vested and expected to vest in the future	3,565		$	25.66	3.8	$	64.6

Summary of Restricted Stock Award Activity

The following table summarizes restricted stock award activity for the three months ended March 30, 2014:

	Number of Shares		Weighted- Average Grant- Date Fair Value
	(In thousands)
Nonvested at December 29, 2013	649		$	29.24
Granted	216		42.55
Vested	(246	)	27.70
Forfeited	(21	)	32.00
Nonvested at March 30, 2014	598		$	34.59