Leases (Assets and Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Leases [Abstract]
ROU assets, net of amortization	$ 168	$ 172
Lease liabilities	193	198
ROU assets, net of amortization	3	3
Finance lease obligations	$ 4	$ 4
Weighted average remaining lease term, operating leases	8 years 7 months 6 days	8 years 8 months 12 days
Weighted average remaining lease term, finance leases	16 years 2 months 12 days	16 years 6 months
Weighted average discount rate, operating leases	3.40%	3.40%
Weighted average discount rate, finance leases	3.10%	3.10%