Credit Quality (Summarizes the Bancorp's Recorded Investment in Portfolio Loans and Leases by Age and Class) (Parenthetical) (Detail) - Residential Mortgage Loans - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due
Portfolio loans and leases at fair value	$ 185	$ 183
Federal Housing Administration Loan
Financing Receivable, Recorded Investment, Past Due
Losses Due To Claim Denials And Curtailments	1
Federal Housing Administration Loan \| 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	79	94
Federal Housing Administration Loan \| 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 269	$ 261

Amount of financing receivable past due.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 80
-URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922355-210448

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919253-210447

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953401-111524

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