Employment Benefit Plans AOCI (Details) - Pension Benefits - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan, Change in Accumulated Other Comprehensive Income Loss [Roll Forward]
Beginning balance	$ 182	$ 228	$ 182
Amortization of net loss	2	1	0
Amortization of prior service credits	0	0	(3)
Actuarial gain (loss)	326	(46)	44
Settlements	(1)	(1)	5
Ending balance	509	182	228
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]
Net gain (loss)	509	182
Pre-tax amount recognized in AOCI	$ 509	$ 182	$ 228

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 reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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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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