Summary of Significant Accounting Policies - Schedule of Derivative Contracts Volume and Prices (Detail)	Jun. 30, 2020 MMBTU bbl $ / MMBTU $ / bbl
Natural Gas Derivatives
Derivative [Line Items]
Volume \| MMBTU	247,594,752
Average price	2.58
Natural Gas Derivatives \| Swap Contracts for Q3 and Q4
Derivative [Line Items]
Volume \| MMBTU	94,011,612
Average price	2.63
Natural Gas Derivatives \| Swap Contracts for 2021
Derivative [Line Items]
Volume \| MMBTU	142,633,140
Average price	2.55
Natural Gas Derivatives \| Swap Contracts for 2022
Derivative [Line Items]
Volume \| MMBTU	10,950,000
Average price	2.53
Natural Gas 3-Way Collar Contracts, in MMBTU
Derivative [Line Items]
Volume \| MMBTU	9,200,000
Ceiling, Average price	2.99
Floor, Average price	2.63
Put, Average price	2.32
Natural Gas 3-Way Collar Contracts, in MMBTU \| Swap Contracts for Q3 and Q4
Derivative [Line Items]
Volume \| MMBTU	9,200,000
Ceiling, Average price	2.99
Floor, Average price	2.63
Put, Average price	2.32
Natural Gas Swaptions Call Contracts
Derivative [Line Items]
Volume \| MMBTU	120,450,000
Average price	2.52
Natural Gas Swaptions Call Contracts \| Swap Contracts for 2021
Derivative [Line Items]
Volume \| MMBTU	71,250,000
Average price	2.52
Natural Gas Swaptions Call Contracts \| Swap Contracts for 2022
Derivative [Line Items]
Volume \| MMBTU	49,200,000
Average price	2.51
Natural Gas 2-Way Collar Contracts
Derivative [Line Items]
Volume \| MMBTU	107,250,000
Ceiling, Average price	2.89
Floor, Average price	2.45
Natural Gas 2-Way Collar Contracts \| Collar Contracts for Q3 and Q4
Derivative [Line Items]
Volume \| MMBTU	8,700,000
Ceiling, Average price	2.92
Floor, Average price	2.43
Natural Gas 2-Way Collar Contracts \| Collar Contracts for 2021
Derivative [Line Items]
Volume \| MMBTU	98,550,000
Ceiling, Average price	2.88
Floor, Average price	2.45
Crude Oil Contracts, in Barrels
Derivative [Line Items]
Volume \| bbl	532,100
Ceiling, Average price \| $ / bbl	63.89
Floor, Average price \| $ / bbl	49.25
Crude Oil Contracts, in Barrels \| Collar Contracts for Q3 and Q4
Derivative [Line Items]
Volume \| bbl	532,100
Ceiling, Average price \| $ / bbl	63.89
Floor, Average price \| $ / bbl	49.25

Derivative average put price.

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- Definition

The average cap rate on a group of price risk derivatives such as caps or collars. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

+ References

No definition available.

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- Definition

The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

+ References

No definition available.

+ Details

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- Definition

The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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