Loans and Leases - Net Charge-Offs (Recoveries) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	$ 139	$ 144	$ 276	$ 254
Commercial \| Commercial and industrial loans
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	69	80	121	115
Commercial \| Commercial mortgage loans
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	3	0	14	0
Commercial \| Commercial leases
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	(1)	0	1	0
Consumer \| Residential mortgage loans
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	(1)	0	(1)	(1)
Consumer \| Home equity
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	0	(1)	1	0
Consumer \| Indirect secured consumer loans
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	16	17	38	42
Consumer \| Credit card
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	15	17	32	36
Consumer \| Solar energy installation loans
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	20	12	38	24
Consumer \| Other consumer loans
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	$ 18	$ 19	$ 32	$ 38