Loans and Leases - Net Charge-Offs (Recoveries) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 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)	$ 110	$ 78
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)	35	30
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	1
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)	24	14
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)	18	15
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	3
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)	$ 21	$ 15