Income Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Alternative minimum tax carryback refund	$ 9,600,000
Income refund receivable	5,600,000
Federal tax benefits	(3,213,000)	(4,038,000)	(5,803,000)
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	8,400,000
Change in unrecognized tax benefits	1,693,000	0	0
Unrecognized tax benefits	8,376,000	9,255,000	3,213,000
Stock Compensation Plan [Member]
Unrecognized Tax Benefits Resulting in Net Operating Loss Carryforward	55,300,000	42,700,000
Operating loss carryforwards	100,000,000
Discrete Events, Including Acquisitions [Member]
Federal tax benefits	19,800,000
Alternative Minimum Tax Credit Carryforward [Member]
Income refund receivable	4,000,000
U.S. Federal [Member]
Operating loss carryforwards	2,500,000,000
Change in unrecognized tax benefits	(3,200,000)
U.S. Federal [Member] | Starting [Member]
Operating loss carryforwards, expiration dates	2021
U.S. Federal [Member] | Ending [Member]
Operating loss carryforwards, expiration dates	2030
State [Member]
Operating loss carryforwards	1,100,000,000
Unrecognized tax benefits	8,400,000
State [Member] | Starting [Member]
Operating loss carryforwards, expiration dates	2012
State [Member] | Ending [Member]
Operating loss carryforwards, expiration dates	2031
Foreign [Member]
Operating loss carryforwards	$ 100,000,000