Consolidated Statements of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011		Dec. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net earnings (loss)	$ 34,200	$ 34,200	[1]	$ 24,800	$ 118,985	$ 113,430	$ 385,405
Other comprehensive income (loss)					799	(524)	7,568
Grant/exercise of stock awards					14,310	9,907	64,150
Stock-based compensation expense					13,908	12,908	32,125
Repurchases of common stock					111,962	215,071	58,225
Dividends, Common Stock, Cash					(12,011)
Stockholders' Equity Attributable to Parent	473,563	449,534		528,884	473,563	449,534	528,884	97,861
Common Stock
Net earnings (loss)					0	0	0
Other comprehensive income (loss)					0	0	0
Grant/exercise of stock awards					0	1	11
Stock-based compensation expense					0	0	0
Repurchases of common stock					0	0	0
Dividends, Common Stock, Cash					0
Stockholders' Equity Attributable to Parent	654	654		653	654	654	653	642
Additional Paid-in Capital
Net earnings (loss)					0	0	0
Other comprehensive income (loss)					0	0	0
Grant/exercise of stock awards					(35,416)	(14,015)	(6,064)
Stock-based compensation expense					13,908	12,908	32,125
Repurchases of common stock					0	0	0
Dividends, Common Stock, Cash					0
Stockholders' Equity Attributable to Parent	102,373	123,881		124,988	102,373	123,881	124,988	98,927
Retained Earnings
Net earnings (loss)					118,985	113,430	385,405
Other comprehensive income (loss)					0	0	0
Grant/exercise of stock awards					0	0	0
Stock-based compensation expense					0	0	0
Repurchases of common stock					0	0	0
Dividends, Common Stock, Cash					(12,011)
Stockholders' Equity Attributable to Parent	1,128,540	1,021,566		908,136	1,128,540	1,021,566	908,136	522,731
Accumulated Other Comprehensive Earnings (Loss)
Net earnings (loss)					0	0	0
Other comprehensive income (loss)					799	(524)	7,568
Grant/exercise of stock awards					0	0	0
Stock-based compensation expense					0	0	0
Repurchases of common stock					0	0	0
Dividends, Common Stock, Cash					0
Stockholders' Equity Attributable to Parent	3,574	2,775		3,299	3,574	2,775	3,299	(4,269)
Treasury Stock
Net earnings (loss)					0	0	0
Other comprehensive income (loss)					0	0	0
Grant/exercise of stock awards					49,726	23,921	70,203
Stock-based compensation expense					0	0	0
Repurchases of common stock					111,962	215,071	58,225
Dividends, Common Stock, Cash					0
Stockholders' Equity Attributable to Parent	$ (761,578)	$ (699,342)		$ (508,192)	$ (761,578)	$ (699,342)	$ (508,192)	$ (520,170)

[1] Includes $4.3 million, net of tax, or $0.09 per common share, diluted, in intangible asset write-offs (see Note 2, Goodwill and Other Intangible Assets, for further information) and $4.2 million, net of tax, or $0.08 per common share, diluted, in restructuring and other postemployment charges