Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash Payments:
Interest	$ 465	$ 825	$ 1,441
Income taxes	607	491	726
Transfers:
Portfolio loans and leases to loans and leases held for sale	447	926	211
Loans and leases held for sale to portfolio loans and leases	49	49	37
Portfolio loans and leases to OREO	8	12	29
Loans and leases held for sale to OREO	0	2	0
Bank premises and equipment to OREO	21	2	30
Supplemental Disclosures:
Net additions to lease liabilities under operating leases	66	47	76
Net additions to lease liabilities under finance leases	35	106	22
Right-of-use assets recognized at adoption of ASU 2016-02	0	0	509
Conversion of outstanding preferred stock issued by a Bancorp subsidiary	0	0	197
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale	447	926	$ 211
Residential mortgage loans \| GNMA loans
Transfers:
Portfolio loans and leases to loans and leases held for sale	167	794
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale	$ 167	$ 794

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