Share-Based Compensation (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Share-Based Compensation [Abstract]
Salaries, wages and employee benefits	$ 316,000	$ 4,224,000	$ 9,485,000	$ 11,119,000
Deferred income tax benefit	(89,000)	(1,632,000)	(3,665,000)	(4,289,000)
Net share-based compensation expense	227,000	2,592,000	5,820,000	6,830,000
Accrued liabilities for cash-settled	$ 1,700,000		$ 1,700,000		$ 2,900,000
Fair value per SAR	$ 6.11		$ 6.11		$ 16.41