Income Taxes - Provision for Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current:
Federal	$ (210)	$ 712	$ (6,681)
State	0	0	0
Total current	(210)	712	(6,681)
Deferred:
Federal	(10,755)	(4,600)	4,756
State	(1,996)	(418)	536
Total deferred	(12,751)	(5,018)	5,292
Increase (decrease) in valuation allowance for deferred tax assets	(11,000)	11,000	0
Total income taxes	$ (23,961)	$ 6,694	$ (1,389)