Goodwill and Other Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	$ 3,872	$ 3,911
Accumulated Amortization	(2,473)	(2,361)
Net Carrying Amount	1,399	1,550
CDI
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	2,410	2,453
Accumulated Amortization	(1,880)	(1,837)
Net Carrying Amount	530	616
Other, primarily client relationship intangibles
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	1,462	1,458
Accumulated Amortization	(593)	(524)
Net Carrying Amount	$ 869	$ 934