Supplemental Cash Flow (Details) - USD ($) $ in Millions		9 Months Ended
Jan. 01, 2020	Sep. 30, 2020	Sep. 30, 2019
Cash Payments:
Interest		$ 746	$ 1,166
Income taxes		419	524
Transfers:
Portfolio loans and leases to loans and leases held for sale		713	191
Loans and leases held for sale to portfolio loans and leases		39	30
Portfolio loans and leases to OREO		11	23
Loans and leases held for sale to OREO		2	0
Supplemental Disclosures:
Additions to lease liabilities under operating leases		41	43
Additions to lease liabilities under finance leases		93	13
Right-of-use assets recognized at adoption of ASU 2016-02		$ 0	$ 509
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Conversion of outstanding preferred stock issued by a Bancorp subsidiary		$ 0	$ 197
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale		713	$ 191
Residential mortgage loans \| GNMA loans
Transfers:
Portfolio loans and leases to loans and leases held for sale		668
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale		$ 668

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