Leases (Lease Cost and Additional Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Leases [Abstract]
Operating lease cost	$ 82	$ 80
Short-term lease cost	1	1
Variable lease cost	26	37
Sublease income	(3)	(4)
Net lease cost	106	114
Operating cash outflows from operating leases	93	94
Right of use assets obtained in exchange for new operating lease liabilities	$ 36	$ 76
Weighted average remaining lease term – real estate	7 years 9 months 18 days	8 years 4 months 24 days
Weighted average discount rate – real estate leases	3.44%	3.12%