Summary of Significant Accounting Policies - Summary of Reconciliation of Amounts in Previously Reported Consolidated Financial Statements - Statement of Operations and Comprehensive Income (Loss) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Quantifying Misstatement In Current Year Financial Statements [Line Items]
Production and ad valorem taxes	$ 2,033	$ 2,203	$ 3,964	$ 4,766
Total operating expenses	80,589	84,017	168,220	184,231
Operating loss	5,602	(36,951)	19,833	(87,559)
Loss before income taxes	11,494	(73,163)	38,341	(118,157)
Net loss	$ 11,494	$ (73,163)	$ 38,341	$ (118,697)
Basic and diluted loss per share		$ (0.33)		$ (0.53)
As Reported [Member]
Quantifying Misstatement In Current Year Financial Statements [Line Items]
Production and ad valorem taxes		$ 2,051		$ (233)
Total operating expenses		83,865		179,232
Operating loss		(36,799)		(82,560)
Loss before income taxes		(73,011)		(113,158)
Net loss		$ (73,011)		$ (113,698)
Basic and diluted loss per share		$ (0.33)		$ (0.51)
Adjustment [Member]
Quantifying Misstatement In Current Year Financial Statements [Line Items]
Production and ad valorem taxes		$ 152		$ 4,999
Total operating expenses		152		4,999
Operating loss		(152)		(4,999)
Loss before income taxes		(152)		(4,999)
Net loss		$ (152)		$ (4,999)
Basic and diluted loss per share				$ (0.02)