Employee Benefits - Pension and Post-Retirement Benefits (Details) - Affiliated Entity - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Pension Plan
Employee Benefits
Employer contributions to benefit plan	$ 170	$ 0
Unfunded status	645	769
Post-Retirement Benefit Plan
Employee Benefits
Unfunded status	$ 1,700	1,900
Pension, Supplemental and Other Postretirement Benefit Plans
Employee Benefits
Pension settlement term	30 years
Revenue from affiliate	$ 52	$ 57

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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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.

+ References

No definition available.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

+ References

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- Definition

Amount of transactions with related party during the financial reporting period.

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