Income Taxes Tax Contingency (Details) (USD $)	3 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance Beginning		$ 6,017,000	$ 4,246,000	$ 5,673,000
Decreases from positions taken in prior years	(1,900,000)	173,000	(18,000)	(33,000)
Increases for positions related to current year		2,062,000	2,563,000	667,000
Lapsing of statutes of limitations		(3,682,000)	(774,000)	(2,061,000)
Balance Ending		4,570,000	6,017,000	4,246,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		4,600,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense		1,300,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued		1,900,000	2,100,000
Scenario, Forecast [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Lapsing of statutes of limitations		$ 1,400,000