Goodwill and Other Intangibles (Amortized Intangible Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Gross Cost	$ 4,466	$ 4,353
Accumulated Amortization	1,958	1,816
Net Carrying Amount	2,508	2,537
Client relationships
Finite-Lived Intangible Assets [Line Items]
Gross Cost	4,096	3,993
Accumulated Amortization	1,631	1,508
Net Carrying Amount	2,465	2,485
Other
Finite-Lived Intangible Assets [Line Items]
Gross Cost	370	360
Accumulated Amortization	327	308
Net Carrying Amount	$ 43	$ 52