Derivative Financial Instruments - Oil Derivative Contracts (Details)	12 Months Ended
Dec. 31, 2020 $ / bbl MBbls
Dated Brent \| January 2021 - December 2021 \| Swaps with sold puts
Derivative Financial Instruments
Volume (mbbls) \| MBbls	6,000
Weighted Average Price per Bbl [Abstract]
Net deferred premium payable/(receivable) (usd per bbll)	0
Swap (usd per bbl)	53.96
Sold Put (usd per bbl)	42.92
Floor (usd per bbl)	0
Ceiling (usd per bbl)	0
Dated Brent \| January 2021 - December 2021 \| Three-way collars
Derivative Financial Instruments
Volume (mbbls) \| MBbls	4,000
Weighted Average Price per Bbl [Abstract]
Net deferred premium payable/(receivable) (usd per bbll)	0.34
Swap (usd per bbl)	0
Sold Put (usd per bbl)	33.13
Floor (usd per bbl)	40.63
Ceiling (usd per bbl)	52.60
Dated Brent \| January 2021 - December 2021 \| Sold calls
Derivative Financial Instruments
Volume (mbbls) \| MBbls	7,000
Weighted Average Price per Bbl [Abstract]
Net deferred premium payable/(receivable) (usd per bbll)	0
Swap (usd per bbl)	0
Sold Put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	70.09
Dated Brent \| January 2022 - December 2022 \| Sold calls
Derivative Financial Instruments
Volume (mbbls) \| MBbls	1,581
Weighted Average Price per Bbl [Abstract]
Net deferred premium payable/(receivable) (usd per bbll)	0
Swap (usd per bbl)	0
Sold Put (usd per bbl)	0
Floor (usd per bbl)	0
Ceiling (usd per bbl)	60.00
NYMEX WTI \| January 2021 - December 2021 \| Three-way collars
Derivative Financial Instruments
Volume (mbbls) \| MBbls	1,000
Weighted Average Price per Bbl [Abstract]
Net deferred premium payable/(receivable) (usd per bbll)	1.00
Swap (usd per bbl)	0
Sold Put (usd per bbl)	37.50
Floor (usd per bbl)	45.00
Ceiling (usd per bbl)	55.00
NYMEX WTI \| January 2021 - June 2021 \| Swaps with sold puts
Derivative Financial Instruments
Volume (mbbls) \| MBbls	1,000
Weighted Average Price per Bbl [Abstract]
Net deferred premium payable/(receivable) (usd per bbll)	0
Swap (usd per bbl)	47.75
Sold Put (usd per bbl)	37.50
Floor (usd per bbl)	0
Ceiling (usd per bbl)	0

Derivative Sold Put Average Price Risk Option Strike Price

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- Definition

Derivative Weighted Average Deferred Premium Per Barrel

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No definition available.

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- Definition

Weighted Average Dated Brent Price Per Bbl [Abstract]

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No definition available.

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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.

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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.

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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.

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No definition available.

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

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No definition available.

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- Definition

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

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No definition available.

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