Risk Management - Credit Risks (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Credit Derivatives [Line Items]
Additional Collateral, Aggregate Fair Value	$ 25
Energy commodity derivative contracts
Credit Derivatives [Line Items]
Letters of credit outstanding	0	$ 0
Cash margin, asset	52
Variation margin, asset	0	0
Variation margin, liability		85
Other Current Liabilities \| Contract and Over the Counter \| Energy commodity derivative contracts
Credit Derivatives [Line Items]
Cash margin		$ 63
Restricted Cash \| Contract and Over the Counter \| Energy commodity derivative contracts
Credit Derivatives [Line Items]
Cash margin, asset	104
Initial margin requirement	52
Variation margin, asset	$ 52

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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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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Amount of deposit for derivative.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of payable for negative price movement on derivative.

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Amount of receivable from positive price movement on derivative.

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