Restatement of Previously Issued Financial Statements - Schedule of Consolidated Statements of Cash Flows from Operating Activities, Including Balances Originally Reported, Corrections and Restated Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net loss	$ (43,485)	$ (98,700)
Depletion, depreciation, and amortization	56,818	51,995
Deferred taxes	(29,191)	19,588
Impairment of oil and gas properties	33,413	35,570
Net cash provided by operating activities	43,446	24,269
As Reported
Cash flows from operating activities:
Net loss	(38,663)	(94,335)
Depletion, depreciation, and amortization	52,718	46,888
Deferred taxes	(29,913)	22,007
Impairment of oil and gas properties	33,413	33,893
Net cash provided by operating activities	43,446	24,269
Correction
Cash flows from operating activities:
Net loss	(4,822)	(4,365)
Depletion, depreciation, and amortization	4,100	5,107
Deferred taxes	$ 722	(2,419)
Impairment of oil and gas properties		$ 1,677