Fair Value Measurement - FV of Commodity Derivatives (Details) - USD ($) $ in Millions |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Offsetting Derivative Assets [Abstract] | ||
| Assets - gross amounts recognized | $ 322 | $ 450 |
| Assets - amounts without right of setoff | 3 | 9 |
| Assets - gross amounts | 319 | 441 |
| Assets - gross amounts offset | 193 | 280 |
| Assets - net amounts presented | 126 | 161 |
| Assets - cash collateral | 4 | 0 |
| Assets - net amounts | 122 | 161 |
| Offsetting Derivative Liabilities [Abstract] | ||
| Liabilities - gross amounts recognized | 311 | 400 |
| Liabilities - amounts without right of setoff | 4 | 4 |
| Liabilities - gross amounts recognized | 307 | 396 |
| Liabilities - gross amounts offset | 193 | 280 |
| Liabilities - net amounts presented | 114 | 116 |
| Liabilities - cash collateral | 12 | 10 |
| Commodity derivatives, liability | $ 102 | $ 106 |
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- Definition Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against an obligation to return collateral. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value, after effects of master netting arrangements, deduction of liabilities not subject to a master netting arrangement and elected not to be offset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against the right to receive collateral. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- References No definition available.
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