Income Taxes - Summary of Income Tax Expense (Benefit) Attributable to Continuing Operations (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation [Line Items]
Federal		$ (1)	$ (6,866)
State
Total current benefit		(1)	(6,866)
Federal	2,721	(2,663)	5,512
State			12
Total deferred (benefit) expense	2,721	(2,663)	5,524
Total current and deferred expense (benefit)	$ 2,721	$ (2,664)	$ (1,342)