Income Taxes - Schedule of Components of Provision Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ 2,500	$ 0	$ 0
State	621	0	0
Totals	3,121	0	0
Deferred:
Federal	32,378	(1,324)	0
State	815	(378)	0
Total income tax provision expense (benefit)	$ 36,314	$ (1,702)	$ 0