Loans and Allowance for Credit Losses - Amortized Cost Basis (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	$ 3,950	$ 5,839
Fiscal year before current fiscal year	3,071	5,104
Two years before current fiscal year	4,969	512
Three years before current fiscal year	459	1,636
Four years before current fiscal year	1,503	1,092
Prior	1,500	668
Revolving Loans	18,662	17,294
Loans, gross, excluding loans classified as held-for-sale	34,114	32,145
Financing receivable, accrued interest, before allowance for credit loss	333	200
Financing receivable, held-for-sale	9	5
Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	29,404	27,176
Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	4,186	4,491
Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	423	379
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	25	99
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	76
Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	31,131	29,160
Commercial and Financial \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	27,116	24,667
Commercial and Financial \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	3,636	4,103
Commercial and Financial \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	324	291
Commercial and Financial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	25	99
Commercial and Financial \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	30
Commercial and Financial \| Domestic
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,758	2,100
Fiscal year before current fiscal year	400	1,164
Two years before current fiscal year	1,081	245
Three years before current fiscal year	203	908
Four years before current fiscal year	767	286
Prior	253	167
Revolving Loans	13,769	13,388
Loans, gross, excluding loans classified as held-for-sale	18,231	18,258
Commercial and Financial \| Domestic \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,408	1,577
Fiscal year before current fiscal year	120	185
Two years before current fiscal year	171	72
Three years before current fiscal year	61	300
Four years before current fiscal year	285	0
Prior	6	9
Revolving Loans	13,516	12,843
Loans, gross, excluding loans classified as held-for-sale	15,567	14,986
Commercial and Financial \| Domestic \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	319	523
Fiscal year before current fiscal year	280	859
Two years before current fiscal year	719	168
Three years before current fiscal year	137	461
Four years before current fiscal year	407	236
Prior	247	151
Revolving Loans	253	545
Loans, gross, excluding loans classified as held-for-sale	2,362	2,943
Commercial and Financial \| Domestic \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	5	0
Fiscal year before current fiscal year	0	120
Two years before current fiscal year	167	0
Three years before current fiscal year	0	105
Four years before current fiscal year	75	19
Prior	0	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	247	244
Commercial and Financial \| Domestic \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	20	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	5
Three years before current fiscal year	5	42
Four years before current fiscal year	0	31
Prior	0	7
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	25	85
Commercial and Financial \| Domestic \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	6
Fiscal year before current fiscal year	0
Two years before current fiscal year	24
Three years before current fiscal year	0
Four years before current fiscal year	0
Prior	0
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	30
Commercial and Financial \| Non-U.S.
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	2,109	3,220
Fiscal year before current fiscal year	2,151	3,328
Two years before current fiscal year	3,360	118
Three years before current fiscal year	107	186
Four years before current fiscal year	195	144
Prior	85	0
Revolving Loans	4,893	3,906
Loans, gross, excluding loans classified as held-for-sale	12,900	10,902
Commercial and Financial \| Non-U.S. \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	1,848	2,986
Fiscal year before current fiscal year	1,994	2,799
Two years before current fiscal year	2,819	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	0	0
Revolving Loans	4,888	3,897
Loans, gross, excluding loans classified as held-for-sale	11,549	9,682
Commercial and Financial \| Non-U.S. \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	261	234
Fiscal year before current fiscal year	157	529
Two years before current fiscal year	512	100
Three years before current fiscal year	78	181
Four years before current fiscal year	190	107
Prior	71	0
Revolving Loans	5	9
Loans, gross, excluding loans classified as held-for-sale	1,274	1,160
Commercial and Financial \| Non-U.S. \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	29	18
Three years before current fiscal year	29	5
Four years before current fiscal year	5	23
Prior	14	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	77	46
Commercial and Financial \| Non-U.S. \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year		0
Fiscal year before current fiscal year		0
Two years before current fiscal year		0
Three years before current fiscal year		0
Four years before current fiscal year		14
Prior		0
Revolving Loans		0
Loans, gross, excluding loans classified as held-for-sale		14
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	2,983	2,985
Commercial real estate \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	2,288	2,509
Commercial real estate \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	550	388
Commercial real estate \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	99	88
Commercial real estate \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	0	0
Commercial real estate \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	46
Commercial real estate \| Domestic
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	83	519
Fiscal year before current fiscal year	520	612
Two years before current fiscal year	528	149
Three years before current fiscal year	149	542
Four years before current fiscal year	541	662
Prior	1,162	501
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	2,983	2,985
Commercial real estate \| Domestic \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	83	519
Fiscal year before current fiscal year	500	612
Two years before current fiscal year	528	100
Three years before current fiscal year	100	330
Four years before current fiscal year	330	511
Prior	747	436
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	2,288	2,508
Commercial real estate \| Domestic \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	0	0
Fiscal year before current fiscal year	20	0
Two years before current fiscal year	0	49
Three years before current fiscal year	49	163
Four years before current fiscal year	189	111
Prior	292	65
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	550	388
Commercial real estate \| Domestic \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	49
Four years before current fiscal year	22	40
Prior	77	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	99	$ 89
Commercial real estate \| Domestic \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	0
Fiscal year before current fiscal year	0
Two years before current fiscal year	0
Three years before current fiscal year	0
Four years before current fiscal year	0
Prior	46
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	$ 46

Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Loss, Excluding Held For Sale Receivables

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Amount, before allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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Amortized cost excluding accrued interest, of financing receivable that can be withdrawn, repaid, and redrawn.

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Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated in current fiscal year. Excludes net investment in lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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