Income Taxes (Details 3) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2011	Dec. 31, 2011	Dec. 31, 2010
Unrecognized tax benefits
Liability for Gross Unrealized Tax Benefits		$ 129,000	$ 3,164,000
Unrecognized tax benefits which if recognized will affect the entity's effective tax rate		84,000	2,200,000
Accrued interest and penalties		19,000	2,700,000
Gross state unrecognized tax benefits which will reverse due to anticipated expirations of time to assess tax		29,000
Company's summary of accounting for tax uncertainties
Balance at the beginning of the period	3,164,000	3,164,000	4,132,000
Additions related to prior year positions		100,000	1,006,000
Reductions related to prior year positions		(450,000)	0
Reductions due to settlements	(2,400,000)	(1,878,000)	0
Reductions due to expiration of the statute of limitations		(807,000)	(1,974,000)
Balance at the end of the period		$ 129,000	$ 3,164,000