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		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Financing Receivable, Modifications
With an ALLL		$ 317		$ 317		$ 382
No Related ALLL		242		242		482
Total		559		559		864
Loans and leases held for sale	[1]	5,203		5,203		4,741
Total portfolio loans and leases	[2],[3]	107,911		107,911		108,782
Nonperforming
Financing Receivable, Modifications
Loans and leases held for sale						5
Restructured loans held for sale		1		1		1
Nonperforming | Government Insured
Financing Receivable, Modifications
Total portfolio loans and leases		26		26		29
Restructured nonaccrual loans and leases		11		11		17
Commercial
Financing Receivable, Modifications
With an ALLL		206		206		274
No Related ALLL		143		143		364
Total		349		349		638
Interest Income Recognized		7	$ 2	25	$ 7
Total portfolio loans and leases		66,720		66,720		68,997
Commercial | Commercial and industrial loans
Financing Receivable, Modifications
With an ALLL		169		169		213
No Related ALLL		124		124		260
Total		293		293		473
Interest Income Recognized		4	2	13	6
Loans and leases held for sale		2		2		230
Total portfolio loans and leases		47,834		47,834		49,665
Commercial | Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
With an ALLL		9		9		20
No Related ALLL		14		14		60
Total		23		23		80
Interest Income Recognized		2	0	9	0
Total portfolio loans and leases		4,786		4,786		4,675
Commercial | Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
With an ALLL		23		23		34
No Related ALLL		4		4		43
Total		27		27		77
Interest Income Recognized		1	0	3	0
Total portfolio loans and leases		5,514		5,514		5,927
Commercial | Commercial construction loans
Financing Receivable, Modifications
With an ALLL		0		0		1
No Related ALLL		0		0		0
Total		0		0		1
Total portfolio loans and leases		5,456		5,456		5,815
Commercial | Commercial leases
Financing Receivable, Modifications
With an ALLL		5		5		6
No Related ALLL		1		1		1
Total		6		6		7
Interest Income Recognized		0	0	0	1
Loans and leases held for sale		0		0		39
Total portfolio loans and leases		3,130		3,130		2,915
Residential Mortgage
Financing Receivable, Modifications
With an ALLL		4		4		11
No Related ALLL		35		35		49
Total		39		39		60
Interest Income Recognized		6	7	19	22
Consumer
Financing Receivable, Modifications
With an ALLL		107		107		97
No Related ALLL		33		33		39
Total		140		140		136
Interest Income Recognized		3	3	9	10
Total portfolio loans and leases		41,191		41,191		39,785
Consumer | Home equity
Financing Receivable, Modifications
With an ALLL		52		52		55
No Related ALLL		26		26		31
Total		78		78		86
Interest Income Recognized		2	2	5	7
Total portfolio loans and leases		4,276		4,276		5,183
Consumer | Home equity | Nonperforming
Financing Receivable, Modifications
Total portfolio loans and leases		78		78		86
Consumer | Indirect secured consumer loans
Financing Receivable, Modifications
With an ALLL		29		29		8
No Related ALLL		7		7		8
Total		36		36		16
Interest Income Recognized		0	0	1	0
Total portfolio loans and leases		16,004		16,004		13,653
Consumer | Indirect secured consumer loans | Nonperforming
Financing Receivable, Modifications
Total portfolio loans and leases		36		36		16
Consumer | Credit card
Financing Receivable, Modifications
With an ALLL		24		24		32
No Related ALLL		0		0		0
Total		24		24		32
Interest Income Recognized		1	1	3	3
Total portfolio loans and leases		1,744		1,744		2,007
Consumer | Credit card | Nonperforming
Financing Receivable, Modifications
Total portfolio loans and leases		24		24		32
Consumer | Other consumer loans
Financing Receivable, Modifications
With an ALLL		2		2		2
No Related ALLL		0		0		0
Total		2		2		2
Total portfolio loans and leases		3,009		3,009		3,014
Consumer | Other consumer loans | Nonperforming
Financing Receivable, Modifications
Total portfolio loans and leases		2		2		2
Nonaccrual Portfolio Loans and Leases
Financing Receivable, Modifications
With an ALLL		317		317		382
No Related ALLL		211		211		452
Total		528		528		834
Interest Income Recognized		16	$ 12	53	$ 39
OREO and Other Repossessed Assets
Financing Receivable, Modifications
With an ALLL		0		0		0
No Related ALLL		31		31		30
Total		$ 31		$ 31		$ 30

[1] Includes $1,532 and $1,481 of residential mortgage loans held for sale measured at fair value at September 30, 2021 and December 31, 2020, respectively.

[2] Includes $156 and $161 of residential mortgage loans measured at fair value at September 30, 2021 and December 31, 2020, respectively.

[3] Includes $27 and $55 of other short-term investments, $383 and $756 of portfolio loans and leases, $(3) and $(7) of ALLL, $2 and $5 of other assets, $1 and $2 of other liabilities, and $325 and $656 of long-term debt from consolidated VIEs that are included in their respective captions above at September 30, 2021 and December 31, 2020, respectively. For further information, refer to Note 12.