Supplemental Cash Flow (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Payments:
Interest	$ 825	$ 1,441	$ 1,016
Income taxes	491	726	359
Transfers:
Portfolio loans and leases to loans and leases held for sale	926	211	275
Loans and leases held for sale to portfolio loans and leases	49	37	95
Portfolio loans and leases to OREO	12	29	39
Loans and leases held for sale to OREO	2	0	0
Supplemental Disclosures:
Additions to lease liabilities under operating leases	56	76	0
Additions to lease liabilities under finance leases	110	24	0
Right-of-use assets recognized at adoption of ASU 2016-02	0	509	0
Conversion of outstanding preferred stock issued by a Bancorp subsidiary	0	197	0
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale	926	$ 211	$ 275
Residential mortgage loans \| GNMA loans
Transfers:
Portfolio loans and leases to loans and leases held for sale	794
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale	$ 794

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