Credit Quality (Summarizes the Bancorp's Recorded Investment in Portfolio Loans and Leases by Age and Class) (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018		Jun. 30, 2017	Jun. 30, 2018		Jun. 30, 2017	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 532	[1]		$ 532	[1]		$ 638	[2]
30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	241	[1],[3]		241	[1],[3]		333	[2],[4]
90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	291	[1],[3]		291	[1],[3]		305	[2],[4]
Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Portfolio loans and leases at fair value	162			162			137
Residential Mortgage Loans | Federal Housing Administration Loan
Financing Receivable, Recorded Investment, Past Due
Losses Due To Claim Denials And Curtailments	1		$ 1	3		$ 3
Residential Mortgage Loans | Federal Housing Administration Loan | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	71			71			95
Residential Mortgage Loans | Federal Housing Administration Loan | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 237			$ 237			$ 290

[1] Excludes $ 162 of residential mortgage loans measured at fair value at June 30, 2018 .

[2] Excludes $ 137 of residential mortgage loans measured at fair value at December 31, 2017 .

[3] Includes accrual and nonaccrual loans and leases.

[4] Includes accrual and nonaccrual loans and leases.