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, 2011	$ 552,980	$ 84	$ 135,668	$ 434,581	$ (17,353)
Beginning Balance, Shares at Dec. 31, 2011	42,223	42,223
Issuance of common stock under stock option plans	13,929	2	13,927
Issuance of common stock under stock option plans, Shares	654	654
Stock-based compensation expense	5,303		5,303
Excess tax benefit from stock option exercises	2,969		2,969
Payment of dividends	(8,985)			(8,985)
Net income	34,049			34,049
Net unrealized gain on available-for-sale investments, net of tax of $200	529				529
Foreign currency translation adjustment, net of tax of ($197)	(9,181)				(9,181)
Ending Balance (unaudited) at Jul. 01, 2012	$ 591,593	$ 86	$ 157,867	$ 459,645	$ (26,005)
Ending Balance, Shares (unaudited) at Jul. 01, 2012	42,877	42,877