Pension and Other Postretirement Benefits - Schedule of Amounts Recognized In Accumulated Other Comprehensive Income (Before Taxes) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	$ 31	$ 31
Total amount recognized in accumulated other comprehensive losses (earnings)	31	31
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	(1)	(1)
Total amount recognized in accumulated other comprehensive losses (earnings)	(1)	(1)
Supplemental Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	2	2
Total amount recognized in accumulated other comprehensive losses (earnings)	$ 2	$ 2