Employment Benefit Plans AOCI (Details) - Pension Benefits - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan, Change in Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance	$ 742	$ 285	$ 226
Amortization of net (gain) loss	(30)	(20)	(34)
Actuarial gain (loss)	(83)	477	93
Settlements	2	0	0
Ending balance	631	742	285
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net gain (loss)	$ 631	$ 742	$ 285

Defined Benefit Plan, Change in Accumulated Other Comprehensive Income Loss [Roll Forward]

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- Definition

Other Comprehensive Income Defined Benefit Plans Settlements

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- Definition

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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- Definition

Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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