Credit Quality (Summarizes the Bancorp's Recorded Investment in Portfolio Loans and Leases by Age and Class) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due
Total portfolio loans and leases	$ 117,852	$ 109,375
Commercial Portfolio Segment
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases	77,638	69,657
Total Past Due	357	301
Total portfolio loans and leases	77,995	69,958
90-Days past Due and Still Accruing	43	26
Commercial Portfolio Segment | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	160	154
Commercial Portfolio Segment | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	197	147
Commercial Portfolio Segment | Commercial and Industrial Loans
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases	57,996	50,305
Total Past Due	254	237
Total portfolio loans and leases	58,250	50,542
90-Days past Due and Still Accruing	13	11
Commercial Portfolio Segment | Commercial and Industrial Loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	120	133
Commercial Portfolio Segment | Commercial and Industrial Loans | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	134	104
Commercial Portfolio Segment | Commercial Mortgage Loans, Owner-Occupied
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases	4,846	4,853
Total Past Due	39	27
Total portfolio loans and leases	4,885	4,880
90-Days past Due and Still Accruing	7	9
Commercial Portfolio Segment | Commercial Mortgage Loans, Owner-Occupied | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	16	4
Commercial Portfolio Segment | Commercial Mortgage Loans, Owner-Occupied | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	23	23
Commercial Portfolio Segment | Commercial Mortgage Loans, Nonowner-Occupied
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases	6,255	6,072
Total Past Due	20	11
Total portfolio loans and leases	6,275	6,083
90-Days past Due and Still Accruing	13	6
Commercial Portfolio Segment | Commercial Mortgage Loans, Nonowner-Occupied | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	6	5
Commercial Portfolio Segment | Commercial Mortgage Loans, Nonowner-Occupied | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	14	6
Commercial Portfolio Segment | Commercial Construction Loans
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases	5,457	5,089
Total Past Due	5	1
Total portfolio loans and leases	5,462	5,090
90-Days past Due and Still Accruing	0	0
Commercial Portfolio Segment | Commercial Construction Loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	4	1
Commercial Portfolio Segment | Commercial Construction Loans | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	1	0
Commercial Portfolio Segment | Commercial Leases
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases	3,084	3,338
Total Past Due	39	25
Total portfolio loans and leases	3,123	3,363
90-Days past Due and Still Accruing	10	0
Commercial Portfolio Segment | Commercial Leases | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	14	11
Commercial Portfolio Segment | Commercial Leases | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 25	14
Residential Mortgage
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases		16,372
Total Past Due		169
Total portfolio loans and leases		16,541
90-Days past Due and Still Accruing		50
Residential Mortgage | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		27
Residential Mortgage | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		142
Consumer Portfolio Segment
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases		38,862
Total Past Due		555
Total portfolio loans and leases		39,417
90-Days past Due and Still Accruing		104
Consumer Portfolio Segment | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		288
Consumer Portfolio Segment | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		267
Consumer Portfolio Segment | Home Equity
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases		5,965
Total Past Due		118
Total portfolio loans and leases		6,083
90-Days past Due and Still Accruing		1
Consumer Portfolio Segment | Home Equity | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		61
Consumer Portfolio Segment | Home Equity | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		57
Consumer Portfolio Segment | Indirect secured consumer loans
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases		11,389
Total Past Due		149
Total portfolio loans and leases		11,538
90-Days past Due and Still Accruing		10
Consumer Portfolio Segment | Indirect secured consumer loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		132
Consumer Portfolio Segment | Indirect secured consumer loans | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		17
Consumer Portfolio Segment | Credit Card
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases		2,434
Total Past Due		98
Total portfolio loans and leases		2,532
90-Days past Due and Still Accruing		42
Consumer Portfolio Segment | Credit Card | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		50
Consumer Portfolio Segment | Credit Card | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		48
Consumer Portfolio Segment | Other Consumer Loans
Financing Receivable, Recorded Investment, Past Due
Current Loans and Leases		2,702
Total Past Due		21
Total portfolio loans and leases		2,723
90-Days past Due and Still Accruing		1
Consumer Portfolio Segment | Other Consumer Loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		18
Consumer Portfolio Segment | Other Consumer Loans | 90 Days and Greater Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due		$ 3