Income Taxes - Schedule of Income Tax (Expense) Benefit in Consolidated Statements of Operations (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components Of Income Tax Expense Benefit [Line Items]
Current	$ (4,760)	$ (2,506)	$ 1,407
Benefit (use) of operating loss carryforward		(2,958)	2,958
Deferred	(2,525)	(5,092)	(1,170)
Applicable income tax benefit/(expense)	$ (7,285)	$ (10,556)	$ 3,195