Asset Quality - Schedule of Consumer Credit Exposure (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 119,011	$ 119,394
Accrued interest	500	417
Total consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current	1,133
Writeoff, current period	1
One year prior	8,988	8,775
Writeoff, one year period	3
Two years prior	12,632	13,193
Writeoff, two year period	3
Three years prior	4,491	4,933
Writeoff, three year period	1
Four years prior	1,403	1,565
Writeoff, four year period	1
Prior	2,406
Writeoff, prior	2
Five years prior		311
Prior		2,490
Revolving Loans Amortized Cost Basis	4,878	5,101
Writeoff, Revolving Loans Amortized Cost Basis	12
Revolving Loans Converted to Term Loans Amortized Cost Basis	526	561
Revolving Loans Converted to Term Loans Amortized Cost Basis, writeoff	1
Total	36,457	36,929
Total commercial loan current period gross write-offs	24
Accrued interest	135	103
Total consumer loans | Real estate — residential mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Current	817
Writeoff, current period	0
One year prior	7,008	6,594
Writeoff, one year period	0
Two years prior	8,905	9,664
Writeoff, two year period	0
Three years prior	2,774	2,884
Writeoff, three year period	0
Four years prior	727	757
Writeoff, four year period	0
Prior	1,405
Writeoff, prior	1
Five years prior		108
Prior		1,393
Revolving Loans Amortized Cost Basis	1	1
Writeoff, Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis, writeoff	0
Total	21,637	21,401
Total commercial loan current period gross write-offs	1
Total consumer loans | Real estate — residential mortgage | 750 and above
Financing Receivable, Credit Quality Indicator [Line Items]
Current	621
One year prior	6,003	5,205
Two years prior	8,037	8,702
Three years prior	2,517	2,584
Four years prior	611	636
Prior	979
Five years prior		64
Prior		978
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	18,768	18,169
Total consumer loans | Real estate — residential mortgage | 660 to 749
Financing Receivable, Credit Quality Indicator [Line Items]
Current	188
One year prior	885	1,286
Two years prior	830	919
Three years prior	239	282
Four years prior	100	106
Prior	271
Five years prior		28
Prior		260
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	2,513	2,881
Total consumer loans | Real estate — residential mortgage | Less than 660
Financing Receivable, Credit Quality Indicator [Line Items]
Current	7
One year prior	55	41
Two years prior	37	42
Three years prior	17	17
Four years prior	16	14
Prior	134
Five years prior		15
Prior		130
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	266	259
Total consumer loans | Real estate — residential mortgage | No Score
Financing Receivable, Credit Quality Indicator [Line Items]
Current	1
One year prior	65	62
Two years prior	1	1
Three years prior	1	1
Four years prior	0	1
Prior	21
Five years prior		1
Prior		25
Revolving Loans Amortized Cost Basis	1	1
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	90	92
Total consumer loans | Home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current	13
Writeoff, current period	1
One year prior	191	247
Writeoff, one year period	0
Two years prior	1,721	1,366
Writeoff, two year period	0
Three years prior	738	955
Writeoff, three year period	0
Four years prior	235	303
Writeoff, four year period	0
Prior	759
Writeoff, prior	0
Five years prior		116
Prior		887
Revolving Loans Amortized Cost Basis	3,346	3,516
Writeoff, Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	526	561
Revolving Loans Converted to Term Loans Amortized Cost Basis, writeoff	1
Total	7,529	7,951
Total commercial loan current period gross write-offs	2
Total consumer loans | Home equity loans | 750 and above
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	108	146
Two years prior	1,436	1,044
Three years prior	542	736
Four years prior	146	207
Prior	486
Five years prior		74
Prior		617
Revolving Loans Amortized Cost Basis	2,135	2,238
Revolving Loans Converted to Term Loans Amortized Cost Basis	373	398
Total	5,226	5,460
Total consumer loans | Home equity loans | 660 to 749
Financing Receivable, Credit Quality Indicator [Line Items]
Current	11
One year prior	73	83
Two years prior	255	291
Three years prior	172	194
Four years prior	71	79
Prior	189
Five years prior		32
Prior		187
Revolving Loans Amortized Cost Basis	916	974
Revolving Loans Converted to Term Loans Amortized Cost Basis	121	126
Total	1,808	1,966
Total consumer loans | Home equity loans | Less than 660
Financing Receivable, Credit Quality Indicator [Line Items]
Current	1
One year prior	10	11
Two years prior	30	31
Three years prior	24	25
Four years prior	18	17
Prior	82
Five years prior		10
Prior		81
Revolving Loans Amortized Cost Basis	291	300
Revolving Loans Converted to Term Loans Amortized Cost Basis	32	37
Total	488	512
Total consumer loans | Home equity loans | No Score
Financing Receivable, Credit Quality Indicator [Line Items]
Current	1
One year prior	0	7
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	2
Five years prior		0
Prior		2
Revolving Loans Amortized Cost Basis	4	4
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	7	13
Total consumer loans | Consumer direct loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current	303
Writeoff, current period	0
One year prior	1,788	1,934
Writeoff, one year period	3
Two years prior	2,006	2,161
Writeoff, two year period	3
Three years prior	979	1,094
Writeoff, three year period	1
Four years prior	441	505
Writeoff, four year period	1
Prior	210
Writeoff, prior	0
Five years prior		87
Prior		169
Revolving Loans Amortized Cost Basis	530	558
Writeoff, Revolving Loans Amortized Cost Basis	3
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis, writeoff	0
Total	6,257	6,508
Total commercial loan current period gross write-offs	11
Total consumer loans | Consumer direct loans | 750 and above
Financing Receivable, Credit Quality Indicator [Line Items]
Current	143
One year prior	1,264	1,291
Two years prior	1,549	1,632
Three years prior	741	811
Four years prior	314	351
Prior	118
Five years prior		45
Prior		97
Revolving Loans Amortized Cost Basis	98	102
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	4,227	4,329
Total consumer loans | Consumer direct loans | 660 to 749
Financing Receivable, Credit Quality Indicator [Line Items]
Current	127
One year prior	418	526
Two years prior	376	434
Three years prior	191	229
Four years prior	99	120
Prior	60
Five years prior		26
Prior		41
Revolving Loans Amortized Cost Basis	199	206
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	1,470	1,582
Total consumer loans | Consumer direct loans | Less than 660
Financing Receivable, Credit Quality Indicator [Line Items]
Current	13
One year prior	61	58
Two years prior	61	63
Three years prior	31	32
Four years prior	17	23
Prior	13
Five years prior		7
Prior		9
Revolving Loans Amortized Cost Basis	55	57
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	251	249
Total consumer loans | Consumer direct loans | No Score
Financing Receivable, Credit Quality Indicator [Line Items]
Current	20
One year prior	45	59
Two years prior	20	32
Three years prior	16	22
Four years prior	11	11
Prior	19
Five years prior		9
Prior		22
Revolving Loans Amortized Cost Basis	178	193
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	309	348
Total consumer loans | Credit cards
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
Writeoff, current period	0
One year prior	0	0
Writeoff, one year period	0
Two years prior	0	0
Writeoff, two year period	0
Three years prior	0	0
Writeoff, three year period	0
Four years prior	0	0
Writeoff, four year period	0
Prior	0
Writeoff, prior	0
Five years prior		0
Prior		0
Revolving Loans Amortized Cost Basis	1,001	1,026
Writeoff, Revolving Loans Amortized Cost Basis	9
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis, writeoff	0
Total	1,001	1,026
Total commercial loan current period gross write-offs	9
Total consumer loans | Credit cards | 750 and above
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0
Five years prior		0
Prior		0
Revolving Loans Amortized Cost Basis	499	524
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	499	524
Total consumer loans | Credit cards | 660 to 749
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0
Five years prior		0
Prior		0
Revolving Loans Amortized Cost Basis	400	402
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	400	402
Total consumer loans | Credit cards | Less than 660
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0
Five years prior		0
Prior		0
Revolving Loans Amortized Cost Basis	101	99
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	101	99
Total consumer loans | Credit cards | No Score
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0
Five years prior		0
Prior		0
Revolving Loans Amortized Cost Basis	1	1
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	1	1
Total consumer loans | Consumer indirect loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
Writeoff, current period	0
One year prior	1	0
Writeoff, one year period	0
Two years prior	0	2
Writeoff, two year period	0
Three years prior	0	0
Writeoff, three year period	0
Four years prior	0	0
Writeoff, four year period	0
Prior	32
Writeoff, prior	1
Five years prior		0
Prior		41
Revolving Loans Amortized Cost Basis	0	0
Writeoff, Revolving Loans Amortized Cost Basis	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis, writeoff	0
Total	33	43
Total commercial loan current period gross write-offs	1
Total consumer loans | Consumer indirect loans | 750 and above
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	1	0
Two years prior	0	2
Three years prior	0	0
Four years prior	0	0
Prior	16
Five years prior		0
Prior		19
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	17	21
Total consumer loans | Consumer indirect loans | 660 to 749
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	12
Five years prior		0
Prior		15
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	12	15
Total consumer loans | Consumer indirect loans | Less than 660
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	4
Five years prior		0
Prior		7
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	4	7
Total consumer loans | Consumer indirect loans | No Score
Financing Receivable, Credit Quality Indicator [Line Items]
Current	0
One year prior	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0
Five years prior		0
Prior		0
Revolving Loans Amortized Cost Basis	0	0
Revolving Loans Converted to Term Loans Amortized Cost Basis	0	0
Total	$ 0	$ 0