Loans, Lending Commitments and Related Allowance for Credit Losses - Loans Held for Investment before Allowance by Credit Quality and Origination Year (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 269,852	$ 226,900
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	6,942	6,631
Current Fiscal Year	165	134
One Year Ago	129	50
Two Years Ago	25	25
Three Years Ago	0	15
Four Years Ago	15
Prior	1	34
Total	7,277	6,889
Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	53,624	39,158
Current Fiscal Year	9,762	3,681
One Year Ago	2,698	2,730
Two Years Ago	1,531	2,188
Three Years Ago	970	198
Four Years Ago	12
Prior	552	887
Total	69,149	48,842
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	34	161
Current Fiscal Year	2,425	2,349
One Year Ago	1,962	1,123
Two Years Ago	562	1,793
Three Years Ago	1,426	1,769
Four Years Ago	938
Prior	692	1,217
Total	8,039	8,412
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	219	180
Current Fiscal Year	10,951	10,451
One Year Ago	9,489	8,410
Two Years Ago	7,601	12,962
Three Years Ago	12,106	12,985
Four Years Ago	12,196
Prior	19,841	21,750
Total	72,403	66,738
Residential real estate \| Less than or equal to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	219	180
Current Fiscal Year	9,900	9,458
One Year Ago	8,571	7,529
Two Years Ago	6,788	11,941
Three Years Ago	11,159	12,094
Four Years Ago	11,361
Prior	18,583	20,355
Total	66,581	61,557
Residential real estate \| Greater than 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	1,051	993
One Year Ago	918	881
Two Years Ago	813	1,021
Three Years Ago	947	891
Four Years Ago	835
Prior	1,258	1,395
Total	5,822	5,181
Residential real estate \| Greater than or equal to 740
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	172	136
Current Fiscal Year	9,096	8,653
One Year Ago	7,825	6,778
Two Years Ago	6,099	10,294
Three Years Ago	9,613	10,510
Four Years Ago	9,906
Prior	15,637	17,088
Total	58,348	53,459
Residential real estate \| 680-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	40	39
Current Fiscal Year	1,666	1,607
One Year Ago	1,480	1,431
Two Years Ago	1,315	2,298
Three Years Ago	2,138	2,247
Four Years Ago	2,086
Prior	3,755	4,171
Total	12,480	11,793
Residential real estate \| Less than or equal to 679
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	7	5
Current Fiscal Year	189	191
One Year Ago	184	201
Two Years Ago	187	370
Three Years Ago	355	228
Four Years Ago	204
Prior	449	491
Total	1,575	1,486
Securities-based lending and Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	100,094	84,325
Current Fiscal Year	3,444	2,463
One Year Ago	2,002	2,058
Two Years Ago	1,762	1,974
Three Years Ago	1,562	652
Four Years Ago	417
Prior	3,703	4,547
Total	112,984	96,019
Securities-based lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	97,840	76,432
Current Fiscal Year	2,437	1,291
One Year Ago	1,132	949
Two Years Ago	655	449
Three Years Ago	132	100
Four Years Ago	0
Prior	245	270
Total	102,441	79,491
Investment grade \| Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	2,362	2,668
Current Fiscal Year	125	76
One Year Ago	79	0
Two Years Ago	0	0
Three Years Ago	0	15
Four Years Ago	15
Prior	0	31
Total	2,581	2,790
Investment grade \| Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	15,709	11,405
Current Fiscal Year	2,514	818
One Year Ago	78	1,371
Two Years Ago	596	279
Three Years Ago	13	0
Four Years Ago	0
Prior	7	100
Total	18,917	13,973
Investment grade \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	34	0
Current Fiscal Year	322	147
One Year Ago	577	351
Two Years Ago	153	305
Three Years Ago	332	166
Four Years Ago	0
Prior	37	0
Total	1,455	969
Investment grade \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	639	6,342
Current Fiscal Year	199	719
One Year Ago	690	424
Two Years Ago	126	472
Three Years Ago	170	14
Four Years Ago	17
Prior	996	1,430
Total	2,837	9,401
Non-investment grade \| Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	4,580	3,963
Current Fiscal Year	40	58
One Year Ago	50	50
Two Years Ago	25	25
Three Years Ago	0	0
Four Years Ago	0
Prior	1	3
Total	4,696	4,099
Non-investment grade \| Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	37,915	27,753
Current Fiscal Year	7,248	2,863
One Year Ago	2,620	1,359
Two Years Ago	935	1,909
Three Years Ago	957	198
Four Years Ago	12
Prior	545	787
Total	50,232	34,869
Non-investment grade \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	161
Current Fiscal Year	2,103	2,202
One Year Ago	1,385	772
Two Years Ago	409	1,488
Three Years Ago	1,094	1,603
Four Years Ago	938
Prior	655	1,217
Total	6,584	7,443
Non-investment grade \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	1,615	1,551
Current Fiscal Year	808	453
One Year Ago	180	685
Two Years Ago	981	1,053
Three Years Ago	1,260	538
Four Years Ago	400
Prior	2,462	2,847
Total	$ 7,706	$ 7,127

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 2: http://www.xbrl.org/2003/role/disclosureRef
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