Impairment Charge (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Impairment Charge (Details) [Abstract]
Impairment charge	$ 7,300	$ 18,900	$ 7,320	$ 18,939
Impairment Charge (Table Details) [Abstract]
Loan write-down			2,569	2,059
Fixed asset disposal			1,172	11,753
Other			3,579	5,127
Total	$ 7,300	$ 18,900	$ 7,320	$ 18,939