Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (USD $) In Thousands	Total	Additional Paid-In Capital	Treasury Stock - Common Stock Voting	Retained Earnings (Deficit)	Accumulated Other Comprehensive Loss	Common Stock Voting	Common Stock Non-Voting
Balance at Dec. 31, 2011	$ 312,439	$ 340,716	$ (25,933)	$ (584)	$ (1,882)	$ 113	$ 9
Net income	39,604			39,604
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(636)				(636)
Unrealized net loss on securities available-for-sale, net of tax	(299)				(299)
Stock-based compensation	6,184	6,184
Exercise of stock options	5,997	5,994				3
Withholding tax payments on restricted stock vesting and stock option exercises	(20,003)	(20,003)
Excess tax benefits from stock-based compensation	13,639	13,639
Conversion of common stock non-voting to stock voting		(15,878)	15,878			2	(2)
Repurchases of common stock	(72,603)	(52,908)	(19,688)				(7)
Cash dividend on common stock	(12,388)			(12,388)
Balance at Sep. 30, 2012	$ 271,934	$ 277,744	$ (29,743)	$ 26,632	$ (2,817)	$ 118