Credit Quality (Summarizes the Bancorp's Recorded Investment in Portfolio Loans and Leases by Age and Class) (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 856	$ 599
30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	442	326
90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	414	273
Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Portfolio loans and leases at fair value	183	179
Residential Mortgage Loans | Federal Housing Administration Loan
Financing Receivable, Recorded Investment, Past Due
Losses Due To Claim Denials And Curtailments	4	5
Residential Mortgage Loans | Federal Housing Administration Loan | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	94	90
Residential Mortgage Loans | Federal Housing Administration Loan | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 261	$ 195