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Derivative Instruments - Schedule of Outstanding Commodity Derivative Instruments (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) MMBTU $ / bbl bbl
Derivative [Line Items]
Fair value assets (liability)	$ (94,091)
Crude oil | 2021 Fixed Price Swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in Bbls) | bbl	9,748,000
Average swap price (in dollars per barrel / dollars per btu) | $ / bbl	42.09
Fair value assets (liability)	$ (59,262)
Crude oil | 2022 Fixed Price Swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in Bbls) | bbl	7,245,000
Average swap price (in dollars per barrel / dollars per btu) | $ / bbl	42.66
Fair value assets (liability)	$ (27,759)
Crude oil | 2023 Fixed Price Swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in Bbls) | bbl	5,265,000
Average swap price (in dollars per barrel / dollars per btu) | $ / bbl	43.57
Fair value assets (liability)	$ (10,054)
Crude oil | 2024 Fixed-price Swaps | NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in Bbls) | bbl	434,000
Average swap price (in dollars per barrel / dollars per btu) | $ / bbl	43.68
Fair value assets (liability)	$ (613)
Natural gas | 2021 Fixed Price Swaps | NYMEX HH
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) | MMBTU	14,600,000
Average swap price (in dollars per barrel / dollars per btu) | $ / bbl	2.84
Fair value assets (liability)	$ 2,785
Natural gas | 2022 Fixed Price Swaps | NYMEX HH
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) | MMBTU	5,430,000
Average swap price (in dollars per barrel / dollars per btu) | $ / bbl	2.82
Fair value assets (liability)	$ 812

X

- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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- Definition

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+ References

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- Definition

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- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

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