Loans and Leases - Net Charge-Offs (Recoveries) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together
Net charge-offs (recoveries)	$ 144	$ 90	$ 254	$ 168
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)	80	32	115	62
Commercial | Commercial construction 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)	0	0	0	1
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)	0	0	(1)	0
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)	(1)	1	0	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)	17	16	42	29
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)	17	16	36	31
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)	12	7	24	9
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)	$ 19	$ 18	$ 38	$ 36