Consolidated Statements Of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Common Stock Held In Treasury [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2013	$ 1,628,811	$ 150	$ 1,377,624	$ (2,179,744)	$ 2,463,648	$ (32,867)
Balance, shares at Dec. 31, 2013		150,224		(70,704)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	28,787				28,787
Other comprehensive income (loss), net of tax	18,357					18,357
Exercise of stock options and vesting of restricted stock units	10,248	2	10,246
Exercise of stock options and vesting of restricted stock units, shares		1,218
Share-based compensation expense	9,164		9,164
Tax benefit (detriment) related to equity compensation plans	928		928
Repurchases of common stock	(17,794)			(17,794)
Repurchases of common stock, shares				(538)
Balance at Mar. 31, 2014	1,678,501	152	1,397,962	(2,197,538)	2,492,435	(14,510)
Balance, shares at Mar. 31, 2014		151,442		(71,242)
Balance at Dec. 31, 2014	1,709,222	153	1,444,705	(2,341,652)	2,609,277	(3,261)
Balance, shares at Dec. 31, 2014		152,451		(74,378)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	29,988				29,988
Other comprehensive income (loss), net of tax	10,559					10,559
Exercise of stock options and vesting of restricted stock units	11,032	1	11,031
Exercise of stock options and vesting of restricted stock units, shares		1,032
Share-based compensation expense	6,668		6,668
Tax benefit (detriment) related to equity compensation plans	3,389		3,389
Repurchases of common stock	(111,758)			(111,758)
Repurchases of common stock, shares				(2,056)
Balance at Mar. 31, 2015	$ 1,659,100	$ 154	$ 1,465,793	$ (2,453,410)	$ 2,639,265	$ 7,298
Balance, shares at Mar. 31, 2015		153,483		(76,434)