Derivative Instruments - Schedule of Outstanding Commodity Derivative Instruments (Detail) $ in Thousands	2 Months Ended	12 Months Ended
Feb. 26, 2020 $ / bbl bbl	Dec. 31, 2019 USD ($) $ / bbl bbl
Derivative [Line Items]
Fair value assets (liability) \| $		$ (18,641)
Crude oil \| 2020 Fixed Price Swaps \| NYMEX WTI
Derivative [Line Items]
Average swap price (in dollars per barrel / dollars per btu)		57.17
Crude oil \| 2020 Two-way Collars \| NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl		3,296,000
Average floor price (in dollars per barrel / dollars per btu)		51.76
Average ceiling price (in dollars per barrel / dollars per btu)		61.76
Fair value assets (liability) \| $		$ (4,743)
Crude oil \| 2020 Three-way Collars \| NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl		5,339,000
Average sub-floor price (in dollars per barrel / dollars per btu)		40.00
Average floor price (in dollars per barrel / dollars per btu)		52.79
Average ceiling price (in dollars per barrel / dollars per btu)		64.06
Fair value assets (liability) \| $		$ (330)
Crude oil \| 2021 Fixed-price Swaps \| NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl		248,000
Fair value assets (liability) \| $		$ 36
Crude oil \| 2021 Two-way Collars \| NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl		248,000
Average floor price (in dollars per barrel / dollars per btu)		50.75
Average ceiling price (in dollars per barrel / dollars per btu)		59.13
Fair value assets (liability) \| $		$ (86)
Crude oil \| 2021 Three-way Collar \| NYMEX WTI
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl		889,000
Average sub-floor price (in dollars per barrel / dollars per btu)		40.00
Average floor price (in dollars per barrel / dollars per btu)		51.04
Average ceiling price (in dollars per barrel / dollars per btu)		63.61
Fair value assets (liability) \| $		$ 569
NYMEX WTI \| Crude oil \| 2020 Fixed Price Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl		6,550,000
Fair value assets (liability) \| $		$ (14,087)
NYMEX WTI \| Crude oil \| 2021 Fixed-price Swaps
Derivative [Line Items]
Average swap price (in dollars per barrel / dollars per btu)		56.05
NYMEX WTI \| Subsequent Event \| Crude oil \| 2020 Fixed Price Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl	6,948,000
Average swap price (in dollars per barrel / dollars per btu)	57.14
NYMEX WTI \| Subsequent Event \| Crude oil \| 2020 Two-way Collars
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl	3,296,000
Average floor price (in dollars per barrel / dollars per btu)	51.99
Average ceiling price (in dollars per barrel / dollars per btu)	61.83
NYMEX WTI \| Subsequent Event \| Crude oil \| 2020 Three-way Collars
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl	6,098,000
Average sub-floor price (in dollars per barrel / dollars per btu)	40.74
Average floor price (in dollars per barrel / dollars per btu)	53.28
Average ceiling price (in dollars per barrel / dollars per btu)	63.88
NYMEX WTI \| Subsequent Event \| Crude oil \| 2021 Fixed-price Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl	310,000
Average swap price (in dollars per barrel / dollars per btu)	56.01
NYMEX WTI \| Subsequent Event \| Crude oil \| 2021 Two-way Collars
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl	248,000
Average floor price (in dollars per barrel / dollars per btu)	51.38
Average ceiling price (in dollars per barrel / dollars per btu)	59.33
NYMEX WTI \| Subsequent Event \| Crude oil \| 2021 Three-way Collar
Derivative [Line Items]
Total notional amount of oil barrels (in bbl) \| bbl	1,313,000
Average sub-floor price (in dollars per barrel / dollars per btu)	40.00
Average floor price (in dollars per barrel / dollars per btu)	50.79
Average ceiling price (in dollars per barrel / dollars per btu)	62.46

Derivative, Sub-Floor 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.

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- 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=118260190&loc=d3e13433-108611

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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 volume used to calculate payments on a derivative instrument.

+ References

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- Definition

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

+ References

No definition available.

+ Details

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