Loans and Allowance for Credit Losses - Amortized Cost Basis (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 8,718	$ 5,572
Year two	2,627	3,020
Year three	1,985	4,685
Year four	3,319	424
Year five	333	1,229
Prior	1,897	1,291
Revolving Loans	24,307	20,410
Loans, gross, excluding loans classified as held-for-sale	43,186	36,631
Accrued interest receivable	327	318
Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	37,800	32,024
Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	4,687	3,995
Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	249	304
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	259	238
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	191	70
Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	40,344	33,562
Commercial and Financial \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	35,831	29,737
Commercial and Financial \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	4,278	3,546
Commercial and Financial \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	187	242
Commercial and Financial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	48	14
Commercial and Financial \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	0	23
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	2,842	3,069
Commercial real estate \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	1,969	2,287
Commercial real estate \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	409	449
Commercial real estate \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	62	62
Commercial real estate \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	211	224
Commercial real estate \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	191	47
Domestic \| Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	3,827	2,019
Year two	406	409
Year three	255	1,128
Year four	488	157
Year five	59	579
Prior	352	146
Revolving Loans	18,180	15,557
Loans, gross, excluding loans classified as held-for-sale	23,567	19,995
Domestic \| Commercial and Financial \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	1,946	1,399
Year two	223	120
Year three	89	199
Year four	47	8
Year five	6	272
Prior	197	5
Revolving Loans	18,044	15,476
Loans, gross, excluding loans classified as held-for-sale	20,552	17,479
Domestic \| Commercial and Financial \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	1,834	615
Year two	173	285
Year three	154	747
Year four	387	149
Year five	53	291
Prior	155	141
Revolving Loans	136	81
Loans, gross, excluding loans classified as held-for-sale	2,892	2,309
Domestic \| Commercial and Financial \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	47	0
Year two	10	4
Year three	0	164
Year four	54	0
Year five	0	16
Prior	0	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	111	184
Domestic \| Commercial and Financial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0
Year two	0
Year three	12
Year four	0
Year five	0
Prior	0
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	12
Domestic \| Commercial and Financial \| 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
Domestic \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	41	216
Year two	216	520
Year three	508	529
Year four	347	150
Year five	228	541
Prior	1,502	1,113
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	2,842	3,069
Domestic \| Commercial real estate \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	41	216
Year two	63	500
Year three	488	498
Year four	278	100
Year five	128	375
Prior	971	598
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	1,969	2,287
Domestic \| Commercial real estate \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	153	20
Year three	20	31
Year four	69	50
Year five	100	49
Prior	67	299
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	409	449
Domestic \| Commercial real estate \| Special mention
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	22
Prior	62	40
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	62	62
Domestic \| Commercial real estate \| 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	95
Prior	211	129
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	211	224
Domestic \| Commercial real estate \| Doubtful
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	0
Prior	191	47
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	191	47
Foreign \| Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	4,850	3,337
Year two	2,005	2,091
Year three	1,222	3,028
Year four	2,484	117
Year five	46	109
Prior	43	32
Revolving Loans	6,127	4,853
Loans, gross, excluding loans classified as held-for-sale	16,777	13,567
Foreign \| Commercial and Financial \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	4,243	2,943
Year two	1,796	1,956
Year three	1,152	2,518
Year four	2,187	0
Year five	0	0
Prior	0	0
Revolving Loans	5,901	4,841
Loans, gross, excluding loans classified as held-for-sale	15,279	12,258
Foreign \| Commercial and Financial \| Speculative
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	607	394
Year two	174	135
Year three	44	481
Year four	246	88
Year five	46	109
Prior	43	18
Revolving Loans	226	12
Loans, gross, excluding loans classified as held-for-sale	1,386	1,237
Foreign \| Commercial and Financial \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	35	0
Year three	26	29
Year four	15	29
Year five	0	0
Prior	0	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	76	58
Foreign \| Commercial and Financial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	36	0
Year five	0	0
Prior	0	14
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	$ 36	$ 14

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
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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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