Credit Quality and the Allowance for Loan and Lease Losses - Summary of the Bancorp's Nonaccrual Loans and Leases by Class (Details) - USD ($) $ in Millions		Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Modifications
With an ALLL		$ 489	$ 469
No Related ALLL		254	219
Total		743	688
Total loans and leases held for sale	[1]	339	378
Nonperforming
Financing Receivable, Modifications
Total loans and leases held for sale		5	1
Nonperforming | Government Insured
Financing Receivable, Modifications
Total		20	19
Commercial
Financing Receivable, Modifications
With an ALLL		296	284
No Related ALLL		76	42
Total		372	326
Commercial | Commercial and industrial loans
Financing Receivable, Modifications
With an ALLL		283	273
No Related ALLL		49	31
Total		332	304
Total loans and leases held for sale		30	41
Commercial | Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
With an ALLL		12	11
No Related ALLL		24	6
Total		36	17
Commercial | Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
With an ALLL		1	0
No Related ALLL		2	3
Total		3	3
Commercial | Commercial construction loans
Financing Receivable, Modifications
With an ALLL		0	0
No Related ALLL		1	1
Total		1	1
Commercial | Commercial leases
Financing Receivable, Modifications
With an ALLL		0	0
No Related ALLL		0	1
Total		0	1
Total loans and leases held for sale		2	3
Residential Mortgage
Financing Receivable, Modifications
With an ALLL		37	26
No Related ALLL		100	98
Total		137	124
Consumer
Financing Receivable, Modifications
With an ALLL		156	159
No Related ALLL		43	40
Total		199	199
Consumer | Home equity
Financing Receivable, Modifications
With an ALLL		22	21
No Related ALLL		38	36
Total		60	57
Consumer | Indirect secured consumer loans
Financing Receivable, Modifications
With an ALLL		27	32
No Related ALLL		5	4
Total		32	36
Consumer | Credit card
Financing Receivable, Modifications
With an ALLL		32	34
No Related ALLL		0	0
Total		32	34
Consumer | Solar energy installation loans
Financing Receivable, Modifications
With an ALLL		65	60
No Related ALLL		0	0
Total		65	60
Consumer | Other consumer loans
Financing Receivable, Modifications
With an ALLL		10	12
No Related ALLL		0	0
Total		10	12
Nonaccrual Portfolio Loans and Leases
Financing Receivable, Modifications
With an ALLL		489	469
No Related ALLL		219	180
Total		708	649
OREO and Other Repossessed Assets
Financing Receivable, Modifications
With an ALLL		0	0
No Related ALLL		35	39
Total		$ 35	$ 39

[1] Includes $307 and $334 of residential mortgage loans held for sale measured at fair value at March 31, 2024 and December 31, 2023, respectively.