Quarterly Results (Unaudited) (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended					12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Quarterly Results (Unaudited) (Textual) [Abstract]
Impairment charges	$ 900	$ 800		$ 2,100	$ 1,200	$ 4,348	$ 3,489	$ 7,699
Agreement charges			500		800	473	845
Uncollectible note receivable	0			0	800	0	0
Income tax (benefit) expense	$ (80,790)					$ (80,790)	$ 10,479	$ (490)