Employee Benefit Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets contributions by employer	$ 4
Defined Benefit Plan, Expected Future Benefit Payment, Remainder of Fiscal Year	13
Total estimated contributions by employer during fiscal year	17
Postretirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets contributions by employer	0
Defined Benefit Plan, Expected Future Benefit Payment, Remainder of Fiscal Year	1
Total estimated contributions by employer during fiscal year	1
Postemployment Retirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net benefit cost	13	$ 6
Plan assets contributions by employer	7
Defined Benefit Plan, Expected Future Benefit Payment, Remainder of Fiscal Year	30
Total estimated contributions by employer during fiscal year	$ 23