Credit Quality and the Allowance for Loan and Lease Losses - Summary of the Credit Risk Profile of the Bancorp's Commercial Portfolio Segment by Class (Details) - USD ($) $ in Millions		Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Modifications
Total	[1],[2]	$ 110,731	$ 109,558
Total loans and leases		108,157	108,356
Commercial
Financing Receivable, Modifications
2020		9,845
2019		4,577
2018		3,209
2017		2,058
2016		1,533
Prior		2,988
Revolving Loans Amortized Cost Basis		47,040
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		71,250	69,958
Total loans and leases		71,250	69,958
Commercial | Pass
Financing Receivable, Modifications
2020		8,871
2019		4,337
2018		2,674
2017		1,854
2016		1,410
Prior		2,691
Revolving Loans Amortized Cost Basis		39,489
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		61,326
Total loans and leases			66,143
Commercial | Special mention
Financing Receivable, Modifications
2020		450
2019		116
2018		146
2017		62
2016		56
Prior		65
Revolving Loans Amortized Cost Basis		4,623
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		5,518
Total loans and leases			1,825
Commercial | Substandard
Financing Receivable, Modifications
2020		524
2019		124
2018		389
2017		142
2016		67
Prior		232
Revolving Loans Amortized Cost Basis		2,916
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		4,394
Total loans and leases			1,944
Commercial | Doubtful
Financing Receivable, Modifications
2020		0
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		12
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		12
Total loans and leases			46
Commercial | Commercial and industrial loans
Financing Receivable, Modifications
2020		7,018
2019		2,473
2018		1,643
2017		976
2016		615
Prior		998
Revolving Loans Amortized Cost Basis		37,972
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		51,695
Total loans and leases		51,695	50,542
Commercial | Commercial and industrial loans | Pass
Financing Receivable, Modifications
2020		6,755
2019		2,329
2018		1,288
2017		849
2016		561
Prior		856
Revolving Loans Amortized Cost Basis		31,689
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		44,327
Total loans and leases			47,671
Commercial | Commercial and industrial loans | Special mention
Financing Receivable, Modifications
2020		96
2019		67
2018		86
2017		40
2016		10
Prior		21
Revolving Loans Amortized Cost Basis		3,661
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		3,981
Total loans and leases			1,423
Commercial | Commercial and industrial loans | Substandard
Financing Receivable, Modifications
2020		167
2019		77
2018		269
2017		87
2016		44
Prior		121
Revolving Loans Amortized Cost Basis		2,610
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		3,375
Total loans and leases			1,406
Commercial | Commercial and industrial loans | Doubtful
Financing Receivable, Modifications
2020		0
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		12
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		12
Total loans and leases			42
Commercial | Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
2020		1,181
2019		737
2018		534
2017		331
2016		284
Prior		541
Revolving Loans Amortized Cost Basis		1,196
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		4,804
Total loans and leases		4,804	4,880
Commercial | Commercial mortgage owner-occupied loans | Pass
Financing Receivable, Modifications
2020		905
2019		693
2018		466
2017		308
2016		258
Prior		489
Revolving Loans Amortized Cost Basis		1,033
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		4,152
Total loans and leases			4,421
Commercial | Commercial mortgage owner-occupied loans | Special mention
Financing Receivable, Modifications
2020		57
2019		8
2018		28
2017		13
2016		12
Prior		16
Revolving Loans Amortized Cost Basis		83
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		217
Total loans and leases			162
Commercial | Commercial mortgage owner-occupied loans | Substandard
Financing Receivable, Modifications
2020		219
2019		36
2018		40
2017		10
2016		14
Prior		36
Revolving Loans Amortized Cost Basis		80
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		435
Total loans and leases			293
Commercial | Commercial mortgage owner-occupied loans | Doubtful
Financing Receivable, Modifications
2020		0
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		0
Total loans and leases			4
Commercial | Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
2020		1,121
2019		873
2018		641
2017		313
2016		278
Prior		454
Revolving Loans Amortized Cost Basis		2,394
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		6,074
Total loans and leases		6,074	6,083
Commercial | Commercial mortgage nonowner-occupied loans | Pass
Financing Receivable, Modifications
2020		738
2019		865
2018		564
2017		298
2016		248
Prior		391
Revolving Loans Amortized Cost Basis		1,818
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		4,922
Total loans and leases			5,866
Commercial | Commercial mortgage nonowner-occupied loans | Special mention
Financing Receivable, Modifications
2020		254
2019		1
2018		16
2017		3
2016		28
Prior		20
Revolving Loans Amortized Cost Basis		402
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		724
Total loans and leases			135
Commercial | Commercial mortgage nonowner-occupied loans | Substandard
Financing Receivable, Modifications
2020		129
2019		7
2018		61
2017		12
2016		2
Prior		43
Revolving Loans Amortized Cost Basis		174
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		428
Total loans and leases			82
Commercial | Commercial mortgage nonowner-occupied loans | Doubtful
Financing Receivable, Modifications
2020		0
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		0
Total loans and leases			0
Commercial | Commercial construction loans
Financing Receivable, Modifications
2020		71
2019		58
2018		28
2017		0
2016		9
Prior		12
Revolving Loans Amortized Cost Basis		5,478
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		5,656
Total loans and leases		5,656	5,090
Commercial | Commercial construction loans | Pass
Financing Receivable, Modifications
2020		26
2019		58
2018		28
2017		0
2016		9
Prior		12
Revolving Loans Amortized Cost Basis		4,949
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		5,082
Total loans and leases			4,963
Commercial | Commercial construction loans | Special mention
Financing Receivable, Modifications
2020		40
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		477
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		517
Total loans and leases			52
Commercial | Commercial construction loans | Substandard
Financing Receivable, Modifications
2020		5
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		52
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		57
Total loans and leases			75
Commercial | Commercial construction loans | Doubtful
Financing Receivable, Modifications
2020		0
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		0
Total loans and leases			0
Commercial | Commercial leases
Financing Receivable, Modifications
2020		454
2019		436
2018		363
2017		438
2016		347
Prior		983
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		3,021
Total loans and leases		3,021	3,363
Commercial | Commercial leases | Pass
Financing Receivable, Modifications
2020		447
2019		392
2018		328
2017		399
2016		334
Prior		943
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		2,843
Total loans and leases			3,222
Commercial | Commercial leases | Special mention
Financing Receivable, Modifications
2020		3
2019		40
2018		16
2017		6
2016		6
Prior		8
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		79
Total loans and leases			53
Commercial | Commercial leases | Substandard
Financing Receivable, Modifications
2020		4
2019		4
2018		19
2017		33
2016		7
Prior		32
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		99
Total loans and leases			88
Commercial | Commercial leases | Doubtful
Financing Receivable, Modifications
2020		0
2019		0
2018		0
2017		0
2016		0
Prior		0
Revolving Loans Amortized Cost Basis		0
Revolving Loans Converted to Term Loans Amortized Cost Basis		0
Total		$ 0
Total loans and leases			$ 0

[1] Includes $174 and $183 of residential mortgage loans measured at fair value at September 30, 2020 and December 31, 2019, respectively.

[2] Includes $61 and $74 of other short-term investments, $887 and $1,354 of portfolio loans and leases, $(9) and $(7) of ALLL, $5 and $8 of other assets, $2 and $2 of other liabilities, and $786 and $1,253 of long-term debt from consolidated VIEs that are included in their respective captions above at September 30, 2020 and December 31, 2019, respectively. For further information refer to Note 13.