Long-Term Debt - Additional Information (Detail)	4 Months Ended	8 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 12, 2016 USD ($)	Sep. 30, 2016	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Debt Disclosure [Line Items]
Interest on borrowings and related fees 1	$ 678,000	$ 36,012,000			$ 92,490,000	$ 91,866,000
Amortization of debt issuance costs 2	226,000	22,189,000			4,749,000	4,197,000
Interest Paid, Capitalized	(25,000)	(183,000)			(6,288,000)	(7,232,000)
Interest Expense	$ 879,000	58,018,000			$ 90,951,000	$ 88,831,000
Maximum borrowing capacity		128,000,000
Required covenant, current ratio	1.00			1.00
Interest Coverage Ratio, Maximum	3.00			3.00
Revolving Credit Facility [Member]
Debt Disclosure [Line Items]
Maximum borrowing capacity		$ 200,000,000
Revolving Credit Facility [Member] | Minimum
Debt Disclosure [Line Items]
Credit facility interest rate option one, applicable margin rate over Adjusted LIBOR	2.00%
Revolving Credit Facility [Member] | Maximum
Debt Disclosure [Line Items]
Credit facility interest rate option one, applicable margin rate over Adjusted LIBOR	3.00%
Credit facility interest rate option two, applicable margin rate		4.00%
Revolving Credit Facility [Member] | Future Period [Member]
Debt Disclosure [Line Items]
Required covenant, debt to EBITDAX ratio	4.00			4.00
Revolving Credit Facility [Member] | Future Period Two [Member]
Debt Disclosure [Line Items]
Required covenant, debt to EBITDAX ratio	3.75			3.75
Revolving Credit Facility [Member] | through maturity
Debt Disclosure [Line Items]
Required covenant, debt to EBITDAX ratio	3.50			3.50
Revolving credit facility
Debt Disclosure [Line Items]
Letter of credit amount outstanding	$ 800,000			$ 800,000
Line of Credit Facility, Interest Rate at Period End	3.67%			3.67%
Commitment fees for undrawn credit facility				0.50%
Revolving credit facility | Letter of Credit
Debt Disclosure [Line Items]
Maximum borrowing capacity	$ 5,000,000			$ 5,000,000
Interest Payable One [Member] | Revolving Credit Facility [Member]
Debt Disclosure [Line Items]
Debt Instrument, Interest Payable Period			1 month
Interest Payable Two [Member] | Revolving Credit Facility [Member]
Debt Disclosure [Line Items]
Debt Instrument, Interest Payable Period			3 months
Interest Payable Three [Member] | Revolving Credit Facility [Member]
Debt Disclosure [Line Items]
Debt Instrument, Interest Payable Period			6 months