Supplemental Oil and Gas Information (Unaudited) - Schedule of Capitalized Costs Relating to Oil and Natural Gas Producing Activities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Extractive Industries [Abstract]
Evaluated oil and natural gas properties	$ 3,115,012	$ 3,616,325	$ 3,329,338
Support equipment and facilities	199,093	205,876	198,088
Accumulated depletion, depreciation, and amortization	(1,743,274)	(1,878,549)	(1,060,114)
Total	$ 1,570,831	$ 1,943,652	$ 2,467,312