Loans and Allowance for Credit Losses - Amortized Cost Basis (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 5,572	$ 5,839
Year two	3,020	5,104
Year three	4,685	512
Year four	424	1,636
Year five	1,229	1,092
Prior	1,291	668
Revolving Loans	20,410	17,294
Loans, gross, excluding loans classified as held-for-sale	36,631	32,145
Accrued interest receivable	318	200
Financing receivable, held-for-sale		5
Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	32,024	27,176
Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	3,995	4,491
Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	304	379
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	238	99
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	70
Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	33,562	29,160
Commercial and Financial \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	29,737	24,667
Commercial and Financial \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	3,546	4,103
Commercial and Financial \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	242	291
Commercial and Financial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	14	99
Commercial and Financial \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	23
Commercial and Financial \| Geographic Distribution, Domestic
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	2,019	2,100
Year two	409	1,164
Year three	1,128	245
Year four	157	908
Year five	579	286
Prior	146	167
Revolving Loans	15,557	13,388
Loans, gross, excluding loans classified as held-for-sale	19,995	18,258
Commercial and Financial \| Geographic Distribution, Domestic \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	1,399	1,577
Year two	120	185
Year three	199	72
Year four	8	300
Year five	272	0
Prior	5	9
Revolving Loans	15,476	12,843
Loans, gross, excluding loans classified as held-for-sale	17,479	14,986
Commercial and Financial \| Geographic Distribution, Domestic \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	615	523
Year two	285	859
Year three	747	168
Year four	149	461
Year five	291	236
Prior	141	151
Revolving Loans	81	545
Loans, gross, excluding loans classified as held-for-sale	2,309	2,943
Commercial and Financial \| Geographic Distribution, Domestic \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	4	120
Year three	164	0
Year four	0	105
Year five	16	19
Prior	0	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	184	244
Commercial and Financial \| Geographic Distribution, Domestic \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one		0
Year two		0
Year three		5
Year four		42
Year five		31
Prior		7
Revolving Loans		0
Loans, gross, excluding loans classified as held-for-sale		85
Commercial and Financial \| Geographic Distribution, Domestic \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	5
Year two	0
Year three	18
Year four	0
Year five	0
Prior	0
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	23
Commercial and Financial \| Non-U.S.
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	3,337	3,220
Year two	2,091	3,328
Year three	3,028	118
Year four	117	186
Year five	109	144
Prior	32	0
Revolving Loans	4,853	3,906
Loans, gross, excluding loans classified as held-for-sale	13,567	10,902
Commercial and Financial \| Non-U.S. \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	2,943	2,986
Year two	1,956	2,799
Year three	2,518	0
Year four	0	0
Year five	0	0
Prior	0	0
Revolving Loans	4,841	3,897
Loans, gross, excluding loans classified as held-for-sale	12,258	9,682
Commercial and Financial \| Non-U.S. \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	394	234
Year two	135	529
Year three	481	100
Year four	88	181
Year five	109	107
Prior	18	0
Revolving Loans	12	9
Loans, gross, excluding loans classified as held-for-sale	1,237	1,160
Commercial and Financial \| Non-U.S. \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	0	0
Year three	29	18
Year four	29	5
Year five	0	23
Prior	0	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	58	46
Commercial and Financial \| Non-U.S. \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	14
Prior	14	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	14	14
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	3,069	2,985
Commercial real estate \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	2,287	2,509
Commercial real estate \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	449	388
Commercial real estate \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	62	88
Commercial real estate \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	224	0
Commercial real estate \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	47
Commercial real estate \| Geographic Distribution, Domestic
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	216	519
Year two	520	612
Year three	529	149
Year four	150	542
Year five	541	662
Prior	1,113	501
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	3,069	2,985
Commercial real estate \| Geographic Distribution, Domestic \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	216	519
Year two	500	612
Year three	498	100
Year four	100	330
Year five	375	511
Prior	598	436
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	2,287	2,508
Commercial real estate \| Geographic Distribution, Domestic \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	20	0
Year three	31	49
Year four	50	163
Year five	49	111
Prior	299	65
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	449	388
Commercial real estate \| Geographic Distribution, Domestic \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	49
Year five	22	40
Prior	40	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	62	$ 89
Commercial real estate \| Geographic Distribution, Domestic \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	95
Prior	129
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	224
Commercial real estate \| Geographic Distribution, Domestic \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	47
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	$ 47

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

No definition available.

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- Definition

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
-Section 50
-Paragraph 3B
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- Definition

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
-SubTopic 20
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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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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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