CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Total	COMMON STOCK:	CAPITAL SURPLUS:	ACCUMULATED OTHER COMPREHENSIVE INCOME:	RETAINED EARNINGS:
Balance at beginning of period at Dec. 31, 2010		$ 146	$ 787,105	$ 47,120
Balance at beginning of period, (in shares) at Dec. 31, 2010		146,183
Net issuances of restricted stock, (in shares)		1,252
Repurchases of common stock, (in shares)		(5,238)
Exercises of stock options, (in shares)		661
Net issuances of restricted stock		1	(1)
Net income	107,298				107,298
Foreign currency translation adjustments, net of tax	(3,597)			(3,597)
Repurchases of common stock		(5)	(33,088)		(107,298)
Cash dividends			(61,016)
Stock-based compensation expense			38,193
Exercise of stock options		1	15,277
Tax impact of equity incentive plans			1,814
Balance at end of period at Sep. 30, 2011		143	748,284	43,523
Balance at end of period, (in shares) at Sep. 30, 2011		142,858
Balance at beginning of period at Dec. 31, 2011	800,505	142	759,476	40,887
Balance at beginning of period, (in shares) at Dec. 31, 2011		142,086
Net issuances of restricted stock, (in shares)		1,264
Repurchases of common stock, (in shares)		(4,521)
Exercises of stock options, (in shares)		1,982
Net issuances of restricted stock		1	(1)
Net income	151,323				151,323
Foreign currency translation adjustments, net of tax	1,832			1,832
Repurchases of common stock		(4)	(7,715)		(121,388)
Cash dividends			(42,614)		(21,250)
Stock-based compensation expense			30,891
Exercise of stock options		2	37,840
Tax impact of equity incentive plans			6,450
Balance at end of period at Sep. 30, 2012	$ 835,872	$ 141	$ 784,327	$ 42,719	$ 8,685
Balance at end of period, (in shares) at Sep. 30, 2012		140,811