Consolidated Statement of Shareholders' Equity (USD $) In Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance at Dec. 31, 2013	$ 643,912	$ 174	$ 211,440	$ 462,131	$ (29,833)
Beginning Balance, Shares at Dec. 31, 2013	86,831	86,831
Issuance of common stock under stock option plans	5,951	0	5,951
Issuance of common stock under stock option plans, shares	396	389
Repurchase of common stock	(14,287)	0		(14,287)
Repurchase of common stock, shares		(380)
Stock-based compensation expense	4,004		4,004
Excess tax benefit from stock option exercises	2,165		2,165
Net income	18,506			18,506
Net unrealized loss on cash flow hedges, net of tax of $16	(199)				(199)
Reclassification adjustments for loss (gain) included in net income	33				33
Net unrealized gain on available-for-sale investments, net of tax of $113	1,019				1,019
Reclassification of net realized gain on the sale of available-for-sale investments	(501)				(501)
Foreign currency translation adjustment, net of tax of $7	445				445
Ending Balance at Mar. 30, 2014	$ 661,048	$ 174	$ 223,560	$ 466,350	$ (29,036)
Ending Balance, Shares at Mar. 30, 2014	86,840	86,840