Income Taxes - Schedule of Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current income taxes:
Federal	$ (1,315)	$ 49,529	$ 26,939
State	1,317	5,728	1,987
Foreign	844	879	513
Total current income tax expense	846	56,136	29,439
Deferred income taxes:
Federal	(38,100)	15,164	(34,620)
State	11,075	10,734	(48)
Total deferred income tax expense (benefit)	(27,025)	25,898	(34,668)
Total income tax expense (benefit)	(26,179)	82,034	(5,229)
Income tax benefit related to discontinued operation	$ 14,200	$ 500	$ 500