Goodwill and Other Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 6,275	$ 6,285
Accumulated Amortization	(2,740)	(2,613)
Net Carrying Amount	3,535	3,672
CDI
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,473	2,473
Accumulated Amortization	(1,465)	(1,403)
Net Carrying Amount	1,008	1,070
Other, primarily client relationship intangibles
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,802	3,812
Accumulated Amortization	(1,275)	(1,210)
Net Carrying Amount	$ 2,527	$ 2,602