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Derivative Instruments - Additional Information (Details) | 2 Months Ended | 12 Months Ended
--- | --- | ---
Feb. 28, 2018 MMBTU $ / bbl bbl | Dec. 31, 2017 MMBTU bbl
Crude oil | 2018 Swaps |  |
Derivative [Line Items] |  |
Total notional amount of oil barrels (in bbl) |  | 13,675,000
Crude oil | 2019 Swaps |  |
Derivative [Line Items] |  |
Total notional amount of oil barrels (in bbl) |  | 4,091,000
Crude oil | 2020 Swaps |  |
Derivative [Line Items] |  |
Total notional amount of oil barrels (in bbl) |  | 279,000
Natural gas | 2018 Swaps |  |
Derivative [Line Items] |  |
Total notional amount of natural gas (in MMBtu) | MMBTU |  | 7,665,000
Subsequent Event | Crude oil | 2018 Swaps |  |
Derivative [Line Items] |  |
Average floor price (in dollars per barrel / dollars per btu) | $ / bbl | 56.16 |
Total notional amount of oil barrels (in bbl) | 756,000 |
Subsequent Event | Crude oil | 2019 Swaps |  |
Derivative [Line Items] |  |
Total notional amount of oil barrels (in bbl) | 2,400,000 |
Subsequent Event | Crude oil | 2020 Swaps |  |
Derivative [Line Items] |  |
Total notional amount of oil barrels (in bbl) | 217,000 |
Subsequent Event | Natural gas | 2018 Swaps |  |
Derivative [Line Items] |  |
Average floor price (in dollars per barrel / dollars per btu) | $ / bbl | 3.03 |
Total notional amount of natural gas (in MMBtu) | MMBTU | 668,000 |

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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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