Employment Benefit Plans AOCI (Details) - Pension Benefits - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan, Change in Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance	$ 509	$ 182	$ 228
Amortization of net loss	3	2	1
Actuarial gain (loss)	(285)	326	(46)
Settlements	(1)	(1)	(1)
Ending balance	226	509	182
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net gain (loss)	226	509
Pre-tax amount recognized in AOCI	$ 226	$ 509	$ 182

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

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Other Comprehensive Income Defined Benefit Plans Settlements

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

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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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