Goodwill and Other Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 6,264	$ 6,285
Accumulated Amortization	(2,861)	(2,613)
Net Carrying Amount	3,403	3,672
CDI
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,473	2,473
Accumulated Amortization	(1,527)	(1,403)
Net Carrying Amount	946	1,070
Other, primarily client relationship intangibles
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,791	3,812
Accumulated Amortization	(1,334)	(1,210)
Net Carrying Amount	$ 2,457	$ 2,602