Loans and Allowance for Credit Losses - Amortized Cost Basis (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 9,876	$ 8,718
Year two	5,566	2,627
Year three	1,024	1,985
Year four	898	3,319
Year five	1,835	333
Prior	1,691	1,897
Revolving Loans	25,800	24,307
Loans, gross, excluding loans classified as held-for-sale	46,690	43,186
Accrued interest receivable	338	327
Loans held-for-sale	92	14
Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	42,256	37,800
Sub-investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	3,798	4,687
Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	242	249
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	213	259
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross, excluding loans classified as held-for-sale	181	191
Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	9,810	8,677
Year two	5,525	2,411
Year three	811	1,477
Year four	550	2,972
Year five	1,486	105
Prior	237	395
Revolving Loans	25,800	24,307
Loans, gross, excluding loans classified as held-for-sale	44,219	40,344
Commercial and Financial \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	8,896	6,189
Year two	4,153	2,019
Year three	692	1,241
Year four	504	2,234
Year five	1,313	6
Prior	119	197
Revolving Loans	25,177	23,945
Loans, gross, excluding loans classified as held-for-sale	40,854	35,831
Commercial and Financial \| Sub-investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	911	2,441
Year two	1,224	347
Year three	109	198
Year four	46	633
Year five	133	99
Prior	111	198
Revolving Loans	623	362
Loans, gross, excluding loans classified as held-for-sale	3,157	4,278
Commercial and Financial \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	3	47
Year two	100	45
Year three	0	26
Year four	0	69
Year five	0	0
Prior	7	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	110	187
Commercial and Financial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	48	0
Year three	0	12
Year four	0	36
Year five	0	0
Prior	0	0
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	48	48
Commercial and Financial \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0
Year two	0
Year three	10
Year four	0
Year five	40
Prior	0
Revolving Loans	0
Loans, gross, excluding loans classified as held-for-sale	50	0
Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	66	41
Year two	41	216
Year three	213	508
Year four	348	347
Year five	349	228
Prior	1,454	1,502
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	2,471	2,842
Commercial Real Estate \| Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	41
Year two	41	63
Year three	166	488
Year four	328	278
Year five	318	128
Prior	549	971
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	1,402	1,969
Commercial Real Estate \| Sub-investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	0
Year two	0	153
Year three	47	20
Year four	0	69
Year five	31	100
Prior	563	67
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	641	409
Commercial Real Estate \| Special mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	66	0
Year two	0	0
Year three	0	0
Year four	20	0
Year five	0	0
Prior	46	62
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	132	62
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	0
Prior	165	211
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	165	211
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	131	191
Revolving Loans	0	0
Loans, gross, excluding loans classified as held-for-sale	$ 131	$ 191

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

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