Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2010
Commitments and Contingencies Disclosure [Line Items]
Operating lease rental expense	$ 7,200,000	$ 8,700,000	$ 9,400,000
Asset retirement obligations	2,621,000	$ 5,890,000	$ 6,437,000
Environmental Compliance
Commitments and Contingencies Disclosure [Line Items]
Asset retirement obligations	2,600,000
Legal Reserve
Commitments and Contingencies Disclosure [Line Items]
Reserve established for contingency matters				$ 900,000
Gathering and Intermediate Transportation [Member]
Commitments and Contingencies Disclosure [Line Items]
Contractual Commitments Future Minimum Payments Due	128,289,000
Contractual Obligation	12.3
Contractual Commitments, Minimum Fee Requirement, Current	5.0
Contractual Commitments Future Minimum Payments Due Current	15,328,000
Contract Drilling
Commitments and Contingencies Disclosure [Line Items]
Contractual Commitments Future Minimum Payments Due	3,984,000
Contractual Obligation	3,400,000
Penalty incurred if agreement terminated as of end of period	2,500,000
Contractual Commitments Future Minimum Payments Due Current	3,984,000
Firm Transportation
Commitments and Contingencies Disclosure [Line Items]
Contractual Commitments Future Minimum Payments Due	14,061,000
Contractual Commitments Future Minimum Payments Due Current	1,098,000
Drilling carry [Member]
Commitments and Contingencies Disclosure [Line Items]
Contractual Commitments Future Minimum Payments Due	10,664,000
Contractual Commitments Future Minimum Payments Due Current	$ 1,900,000
Maximum | Firm Transportation
Commitments and Contingencies Disclosure [Line Items]
Contract term	13 years
Minimum | Firm Transportation
Commitments and Contingencies Disclosure [Line Items]
Contract term	1 year
Contract Drilling
Commitments and Contingencies Disclosure [Line Items]
Contractual Obligation	$ 600,000
Contract Obligation, Early Termination Fee	$ 5,900,000