Condensed Consolidated Statements of Changes in Common Stockholders' Equity (USD $) In Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Foreign Currency Translation Adjustment	Unrealized Holding Gains/(Losses)	Other Change in Stockholders Equity [Member]	Total Stockholders Equity
Balance, at Dec. 31, 2010		$ 150	$ (892,012)	$ 1,963,092	$ (204,926)	$ 21,094	$ (27,857)	$ 239	$ 859,780
Net (loss) income	423,689				423,689				423,689
Net foreign currency translation adjustment, net of tax	(21,080)					(21,080)			(21,080)
Net unrealized gain on investments, net of tax	23,593						23,593		23,593
Repurchases of common stock under incentive plans			(40)	0					(40)
Issuance of common stock under benefit plans		1		707					708
Amortization of restricted stock				1,665					1,665
Additional convertible debt issuance costs, net				(22)					(22)
Stock-based compensation expense				1,144					1,144
Dividends declared				(333)	(668)				(1,001)
Balance, at Sep. 30, 2011		151	(892,052)	1,966,253	218,095	14	(4,264)	239	1,288,436
Balance, at Dec. 31, 2011	1,182,291	151	(892,052)	1,966,565	96,227	54	11,471	(125)	1,182,291
Net (loss) income	(274,166)				(274,166)				(274,166)
Net foreign currency translation adjustment, net of tax	(7)					(7)			(7)
Net unrealized gain on investments, net of tax	6,497						6,497		6,497
Repurchases of common stock under incentive plans			(42)						(42)
Issuance of common stock under benefit plans		0		468					468
Amortization of restricted stock				1,311					1,311
Stock-based compensation expense				(98)					(98)
Dividends declared				(1,001)	0				(1,001)
Balance, at Sep. 30, 2012	$ 915,253	$ 151	$ (892,094)	$ 1,967,245	$ (177,939)	$ 47	$ 17,968	$ (125)	$ 915,253