Income Taxes - Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current tax provision:
U.S. Federal	$ 8,579	$ (5,444)	$ (6,004)
State and other	47	(1,569)	(2,066)
Total	8,626	(7,013)	(8,070)
Deferred tax provision:
U.S. Federal	(38,366)	(2,772)	1,148
State and other	(2,895)	1,128	(286)
Total	(41,261)	(1,644)	862
Income tax expense	$ (32,635)	$ (8,657)	$ (7,208)