Income Taxes - Summary of (Benefit) Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal, Current	$ (637)	$ (19,856)	$ 60
Current State and Local Tax Expense (Benefit)	198	51	79
Foreign, Current	1,749	1,674	1,633
Current, Total	1,310	(18,131)	1,772
Federal, Deferred	(483,681)	(309,423)	5,081
State, Deferred	(14,973)	(1,431)	1,275
Deferred, Total	(498,654)	(310,854)	6,356
Income tax benefit (provision), total	$ (497,344)	$ (328,985)	$ 8,128