Income Taxes - Summary of Total Tax Expense (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	$ 6	$ (1,171)	$ 25
State	0	34	73
Current Income Tax Expense (Benefit)	$ 6	$ (1,137)	$ 98