Dispositions (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Components of income from discontinued operations
Income (loss) from discontinued operations, net of tax	$ (16,237)	$ 5,626
Segment Discontinued Operations [Member]
Components of income from discontinued operations
Revenues	16,235	28,985
Income (loss) from discontinued operations before income tax	(6,735)	6,139
Income tax expense (benefit)	(1,227)	2,220
Gain (loss) on disposition, net of tax	(10,729)	1,707
Income (loss) from discontinued operations, net of tax	$ (16,237)	$ 5,626