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Derivative Instruments - Narrative (Details) $ in Millions |  |  | 1 Months Ended | 2 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Mar. 08, 2021 $ / bbl bbl | Nov. 04, 2020 $ / bbl bbl MMBbls | Jun. 30, 2020 USD ($) | Nov. 19, 2020 USD ($) | Dec. 31, 2020 bbl
Crude oil | Three-way Costless Collar Contracts |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Derivative settlements | $ |  |  | $ 25.3 | $ 37.4 |
Crude oil | 2021 Fixed Price Swaps | NYMEX WTI |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) |  |  |  |  | 9,748,000
Crude oil | 2022 Fixed Price Swaps | NYMEX WTI |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) |  |  |  |  | 7,245,000
Subsequent Event |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Average floor price (in usd per barrel / dollars per btu) | $ / bbl | 45.00 |  |  |  |
Subsequent Event | Crude oil | 2021 Fixed Price Swaps | NYMEX WTI |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) | 459,000 |  |  |  |
Subsequent Event | Crude oil | 2022 Fixed Price Swaps | NYMEX WTI |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) | 636,000 |  |  |  |
Minimum | Minimum Hedge Volume Commitment, Year One |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) | MMBbls |  | 10,303 |  |  |
Minimum target price (in usd per bbl) | $ / bbl |  | 43.04 |  |  |
Minimum | Minimum Hedge Volume Commitment, Year Two |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) |  | 6,761 |  |  |
Minimum target price (in usd per bbl) | $ / bbl |  | 43.94 |  |  |
Minimum | Minimum Hedge Volume Commitment, Year Three |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Total notional amount of oil barrels (in Bbls) |  | 4,945 |  |  |
Minimum target price (in usd per bbl) | $ / bbl |  | 44.79 |  |  |

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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 Floor rate on a price risk derivative such as a floor or a collar. 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 cash inflow provided by derivative instruments during the period, which are classified as investing activities, excluding those designated as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585 + Details
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