Derivative Instruments - Summary of Derivative Instrument Positions for Future Production Periods (Detail)	9 Months Ended
	Sep. 30, 2015 MMBTU $ / MMBTU bbl
Swap [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	25,000
Weighted Average Price ($/MMBtu)	(1.21)
Swap [Member] | Natural Gas Derivatives [Member] | Production Period November 2015 - March 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	20,000
Weighted Average Price ($/MMBtu)	0.83
Put Option [Member] | Put Purchased [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	16,800
Weighted Average Price ($/MMBtu)	3.35
Put Option [Member] | Put Purchased [Member] | Floor [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 - December 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	15,000
Weighted Average Price ($/MMBtu)	3.60
Put Option [Member] | Put Purchased [Member] | Floor [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	40,000
Weighted Average Price ($/MMBtu)	2.90
Put Option [Member] | Put Purchased [Member] | Floor [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	30,000
Weighted Average Price ($/MMBtu)	3.00
Put Option [Member] | Put Purchased [Member] | Floor [Member] | Production Period October 2015 - February 2016 [Member] | Oil Derivatives [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (Bbls/d) | bbl	3,000
Weighted Average Price ($/MMBtu)	55.00
Put Option [Member] | Put Purchased [Member] | Floor [Member] | Production Period March 2016 - December 2016 [Member] | Oil Derivatives [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (Bbls/d) | bbl	1,000
Weighted Average Price ($/MMBtu)	60.00
Put Option [Member] | Put Sold [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 - December 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	16,800
Weighted Average Price ($/MMBtu)	3.35
Put Option [Member] | Put Sold [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	16,800
Weighted Average Price ($/MMBtu)	2.87
Put Option [Member] | Put Sold [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	16,800
Weighted Average Price ($/MMBtu)	2.75
Put Option [Member] | Put Sold [Member] | Floor [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 - December 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	15,000
Weighted Average Price ($/MMBtu)	3.00
Put Option [Member] | Put Sold [Member] | Floor [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	40,000
Weighted Average Price ($/MMBtu)	2.35
Put Option [Member] | Put Sold [Member] | Floor [Member] | Production Period March 2016 - December 2016 [Member] | Oil Derivatives [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (Bbls/d) | bbl	1,000
Weighted Average Price ($/MMBtu)	45.00
Call Option [Member] | Put Sold [Member] | Natural Gas Derivatives [Member] | Production Period January 2018 - December 2018 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	40,000
Weighted Average Price ($/MMBtu)	(3.75)
Call Option [Member] | Put Sold [Member] | Ceiling [Member] | Natural Gas Derivatives [Member] | Production Period October 2015 - December 2015 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	15,000
Weighted Average Price ($/MMBtu)	3.80
Call Option [Member] | Put Sold [Member] | Ceiling [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	30,000
Weighted Average Price ($/MMBtu)	3.50
Call Option [Member] | Put Sold [Member] | Ceiling [Member] | Production Period October 2015 - February 2016 [Member] | Oil Derivatives [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (Bbls/d) | bbl	3,000
Weighted Average Price ($/MMBtu)	61.40
Call Option [Member] | Put Sold [Member] | Ceiling [Member] | Production Period March 2016 - December 2016 [Member] | Oil Derivatives [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (Bbls/d) | bbl	1,000
Weighted Average Price ($/MMBtu)	70.10
Call Option [Member] | Put Sold [Member] | Ceiling One [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	20,000
Weighted Average Price ($/MMBtu)	3.25
Call Option [Member] | Put Sold [Member] | Ceiling Two [Member] | Natural Gas Derivatives [Member] | Production Period January 2016 - December 2016 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (MMBtu/d) | MMBTU	20,000
Weighted Average Price ($/MMBtu)	3.22