Credit Quality and the Allowance for Loan and Lease Losses - Summary of the Amortized Cost Basis of the Bancorp's Collateral Dependent Loans (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Impaired
Total portfolio loans and leases	$ 690	$ 705
Commercial
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	572	579
Commercial | Commercial and industrial loans
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	470	467
Commercial | Commercial mortgage owner-occupied loans
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	15	22
Commercial | Commercial mortgage nonowner-occupied loans
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	28	31
Commercial | Commercial construction loans
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	56	56
Commercial | Commercial leases
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	3	3
Residential Mortgage
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	57	60
Consumer
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	61	66
Consumer | Home equity
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	54	58
Consumer | Indirect secured consumer loans
Financing Receivable, Impaired
Loans and leases receivable, allowance for amortized cost basis	$ 7	$ 8