Risk Management and Derivative Instruments - Open Commodity Positions (Detail)	12 Months Ended
	Dec. 31, 2016 MMBTU $ / MMBTU $ / bbl bbl
Natural Gas Derivative Contracts Fixed Price Swap 2017 [Member]
Derivative [Line Items]
Average Monthly Volume (MMBtu) | MMBTU	1,890,000
Weighted-average fixed price | $ / MMBTU	3.86
Crude Oil Derivative Contracts Fixed Price Swap 2017 [Member]
Derivative [Line Items]
Weighted-average fixed price | $ / bbl	84.29
Average Monthly Volume (Bbls) | bbl	184,500
NGL Derivative Contracts Fixed Price Swap 2017 [Member]
Derivative [Line Items]
Weighted-average fixed price | $ / bbl	37.55
Average Monthly Volume (Bbls) | bbl	43,300
Natural Gas Derivative Contracts Fixed Price Swap 2018 [Member]
Derivative [Line Items]
Average Monthly Volume (MMBtu) | MMBTU	1,740,000
Weighted-average fixed price | $ / MMBTU	3.83
Crude Oil Derivative Contracts Fixed Price Swap 2018 [Member]
Derivative [Line Items]
Weighted-average fixed price | $ / bbl	83.44
Average Monthly Volume (Bbls) | bbl	182,000
NGL Derivative Contracts Fixed Price Swap Contracts 2018 [Member]
Derivative [Line Items]
Weighted-average fixed price | $ / bbl	0
Average Monthly Volume (Bbls) | bbl	0
Natural Gas Derivative Contracts Fixed Price Swap 2019 [Member]
Derivative [Line Items]
Average Monthly Volume (MMBtu) | MMBTU	1,000,000
Weighted-average fixed price | $ / MMBTU	3.47
Crude Oil Derivative Contracts Fixed Price Swap 2019 [Member]
Derivative [Line Items]
Weighted-average fixed price | $ / bbl	86.84
Average Monthly Volume (Bbls) | bbl	70,000
NGL Derivative Contracts Fixed Price Swap Contracts 2019 [Member]
Derivative [Line Items]
Weighted-average fixed price | $ / bbl	0
Average Monthly Volume (Bbls) | bbl	0