Credit Quality (Summary of the Bancorp's Nonaccrual Loans and Leases by Class) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Modifications
With an ALLL	$ 460
No Related ALLL	249
Total NPL	709
Interest Income Recognized	14
Nonaccrual portfolio loans and leases		$ 618
OREO and other repossessed personal property		62
Nonperforming Portfolio Assets		680
Commercial Portfolio Segment
Financing Receivable, Modifications
With an ALLL	320
No Related ALLL	125
Total NPL	445
Interest Income Recognized	2
Nonaccrual portfolio loans and leases		397
Commercial Portfolio Segment \| Commercial and Industrial Loans
Financing Receivable, Modifications
With an ALLL	225
No Related ALLL	108
Total NPL	333
Interest Income Recognized	1
Nonaccrual portfolio loans and leases		338
Commercial Portfolio Segment \| Commercial Mortgage Loans, Owner-Occupied
Financing Receivable, Modifications
With an ALLL	17
No Related ALLL	15
Total NPL	32
Interest Income Recognized	0
Nonaccrual portfolio loans and leases		29
Commercial Portfolio Segment \| Commercial Mortgage Loans, Nonowner-Occupied
Financing Receivable, Modifications
With an ALLL	60
No Related ALLL	0
Total NPL	60
Interest Income Recognized	0
Nonaccrual portfolio loans and leases		1
Commercial Portfolio Segment \| Commercial Construction Loans
Financing Receivable, Modifications
With an ALLL	1
No Related ALLL	0
Total NPL	1
Interest Income Recognized	0
Nonaccrual portfolio loans and leases		1
Commercial Portfolio Segment \| Commercial Leases
Financing Receivable, Modifications
With an ALLL	17
No Related ALLL	2
Total NPL	19
Interest Income Recognized	1
Nonaccrual portfolio loans and leases		28
Residential Mortgage Loans
Financing Receivable, Modifications
With an ALLL	28
No Related ALLL	45
Total NPL	73
Interest Income Recognized	8
Nonaccrual portfolio loans and leases		91
Consumer Portfolio Segment
Financing Receivable, Modifications
With an ALLL	112
No Related ALLL	17
Total NPL	129
Interest Income Recognized	4
Nonaccrual portfolio loans and leases		130
Consumer Portfolio Segment \| Home Equity
Financing Receivable, Modifications
With an ALLL	73
No Related ALLL	17
Total NPL	90
Interest Income Recognized	3
Nonaccrual portfolio loans and leases		94
Consumer Portfolio Segment \| Indirect secured consumer loans
Financing Receivable, Modifications
With an ALLL	8
No Related ALLL	0
Total NPL	8
Interest Income Recognized	0
Nonaccrual portfolio loans and leases		7
Consumer Portfolio Segment \| Credit Card
Financing Receivable, Modifications
With an ALLL	29
No Related ALLL	0
Total NPL	29
Interest Income Recognized	1
Nonaccrual portfolio loans and leases		27
Consumer Portfolio Segment \| Other Consumer Loans
Financing Receivable, Modifications
With an ALLL	2
No Related ALLL	0
Total NPL	2
Interest Income Recognized	0
Nonaccrual portfolio loans and leases		$ 2
Nonaccrual Portfolio Loans And Leases
Financing Receivable, Modifications
With an ALLL	460
No Related ALLL	187
Total NPL	647
Interest Income Recognized	14
OREO and Other Repossessed Assets
Financing Receivable, Modifications
With an ALLL	0
No Related ALLL	62
Total NPL	62
Interest Income Recognized	$ 0

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