Credit Quality (Summarizes the Bancorp's Recorded Investment in Impaired Loans and Related Allowance by Class) (Parenthetical) (Detail)		12 Months Ended
		Dec. 31, 2018 USD ($)		Dec. 31, 2017 USD ($)		Dec. 31, 2016
Financing Receivable, Impaired
Unpaid Principal Balance		$ 1,382,000,000		$ 1,679,000,000
Recorded Investment		1,291,000,000	[1]	1,545,000,000	[2]
Allowance		$ 141,000,000		$ 200,000,000
Number of Contracts	[3],[4]	8,869		9,256		10,978
Commercial Portfolio Segment | Commercial and Industrial Loans
Financing Receivable, Impaired
Allowance		$ 34,000,000		$ 87,000,000
Number of Contracts	[3],[4]	54		75		74
Commercial Portfolio Segment | Commercial Mortgage Loans, Owner-Occupied
Financing Receivable, Impaired
Allowance		$ 1,000,000		$ 7,000,000
Number of Contracts	[3],[4]	6		9		12
Commercial Portfolio Segment | Commercial Mortgage Loans, Nonowner-Occupied
Financing Receivable, Impaired
Allowance		$ 0		$ 0
Number of Contracts	[3],[4]	3		4		4
Commercial Portfolio Segment | Troubled Debt Restructuring On Accrual Status
Financing Receivable, Impaired
Unpaid Principal Balance		$ 60,000,000		$ 249,000,000
Commercial Portfolio Segment | Troubled Debt Restructuring On Nonaccrual Status
Financing Receivable, Impaired
Unpaid Principal Balance		147,000,000		150,000,000
Residential Portfolio Segment
Financing Receivable, Impaired
Allowance		$ 61,000,000		$ 64,000,000
Number of Contracts	[3],[4]	1,128		830		924
Residential Portfolio Segment | Troubled Debt Restructuring On Accrual Status
Financing Receivable, Impaired
Unpaid Principal Balance		$ 724,000,000		$ 652,000,000
Residential Portfolio Segment | Troubled Debt Restructuring On Nonaccrual Status
Financing Receivable, Impaired
Unpaid Principal Balance		12,000,000		13,000,000
Consumer Portfolio Segment | Troubled Debt Restructuring On Accrual Status
Financing Receivable, Impaired
Unpaid Principal Balance		237,000,000		275,000,000
Consumer Portfolio Segment | Troubled Debt Restructuring On Nonaccrual Status
Financing Receivable, Impaired
Unpaid Principal Balance		$ 41,000,000		$ 45,000,000

[1] Includes $ 60 , $ 724 and $ 237 , respectively, of commercial, residential mortgage and consumer portfolio TDRs on accrual status and $ 147 , $ 12 and $ 41 , respectively, of commercial, residential mortgage and consumer portfolio TDRs on nonaccrual status at December 31, 2018 .

[2] Includes $ 249 , $ 652 and $ 275 , respectively, of commercial, residential mortgage and consumer portfolio TDRs on accrual status and $ 150 , $ 13 and $ 45 , respectively, of commercial, residential mortgage and consumer portfolio TDRs on nonaccrual status at December 31, 2017

[3] Represents number of loans post-modification and excludes loans previously modified in a TDR .

[4] Excludes all loans and leases held for sale and loans acquired with deteriorated credit quality which were accounted for within a pool .