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	Mar. 31, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 277,857	$ 269,852
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	8,555	6,942
Current Fiscal Year	152	165
One Year Ago	35	129
Two Years Ago	129	25
Three Years Ago	25	0
Four Years Ago	0
Prior	15	16
Total	8,911	7,277
Corporate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	3,226	2,362
Current Fiscal Year	34	125
One Year Ago	0	79
Two Years Ago	79	0
Three Years Ago	0	0
Four Years Ago	0
Prior	15	15
Total	3,354	2,581
Corporate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	5,329	4,580
Current Fiscal Year	118	40
One Year Ago	35	50
Two Years Ago	50	25
Three Years Ago	25	0
Four Years Ago	0
Prior	0	1
Total	5,557	4,696
Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	54,214	53,624
Current Fiscal Year	2,368	9,762
One Year Ago	9,368	2,698
Two Years Ago	1,736	1,531
Three Years Ago	970	970
Four Years Ago	852
Prior	525	564
Total	70,033	69,149
Secured lending facilities \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	15,118	15,709
Current Fiscal Year	481	2,514
One Year Ago	1,777	78
Two Years Ago	48	596
Three Years Ago	269	13
Four Years Ago	9
Prior	11	7
Total	17,713	18,917
Secured lending facilities \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	39,096	37,915
Current Fiscal Year	1,887	7,248
One Year Ago	7,591	2,620
Two Years Ago	1,688	935
Three Years Ago	701	957
Four Years Ago	843
Prior	514	557
Total	52,320	50,232
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	33	34
Current Fiscal Year	730	2,425
One Year Ago	2,197	1,962
Two Years Ago	1,952	562
Three Years Ago	557	1,426
Four Years Ago	1,400
Prior	1,431	1,630
Total	8,300	8,039
Commercial real estate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	33	34
Current Fiscal Year	0	322
One Year Ago	317	577
Two Years Ago	568	153
Three Years Ago	153	332
Four Years Ago	236
Prior	36	37
Total	1,343	1,455
Commercial real estate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	730	2,103
One Year Ago	1,880	1,385
Two Years Ago	1,384	409
Three Years Ago	404	1,094
Four Years Ago	1,164
Prior	1,395	1,593
Total	6,957	6,584
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	231	219
Current Fiscal Year	2,675	10,951
One Year Ago	10,692	9,489
Two Years Ago	9,186	7,601
Three Years Ago	7,391	12,106
Four Years Ago	11,857
Prior	31,497	32,037
Total	73,529	72,403
Residential real estate \| Less than or equal to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	231	219
Current Fiscal Year	2,431	9,900
One Year Ago	9,662	8,571
Two Years Ago	8,293	6,788
Three Years Ago	6,600	11,159
Four Years Ago	10,928
Prior	29,451	29,944
Total	67,596	66,581
Residential real estate \| Greater than 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	244	1,051
One Year Ago	1,030	918
Two Years Ago	893	813
Three Years Ago	791	947
Four Years Ago	929
Prior	2,046	2,093
Total	5,933	5,822
Residential real estate \| Greater than or equal to 740
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	181	172
Current Fiscal Year	2,214	9,096
One Year Ago	8,862	7,825
Two Years Ago	7,563	6,099
Three Years Ago	5,924	9,613
Four Years Ago	9,399
Prior	25,129	25,543
Total	59,272	58,348
Residential real estate \| 680-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	43	40
Current Fiscal Year	407	1,666
One Year Ago	1,648	1,480
Two Years Ago	1,448	1,315
Three Years Ago	1,282	2,138
Four Years Ago	2,106
Prior	5,726	5,841
Total	12,660	12,480
Residential real estate \| Less than or equal to 679
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	7	7
Current Fiscal Year	54	189
One Year Ago	182	184
Two Years Ago	175	187
Three Years Ago	185	355
Four Years Ago	352
Prior	642	653
Total	1,597	1,575
Securities-based lending and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	103,999	100,094
Current Fiscal Year	686	3,444
One Year Ago	3,241	2,002
Two Years Ago	1,882	1,762
Three Years Ago	1,703	1,562
Four Years Ago	1,478
Prior	4,095	4,120
Total	117,084	112,984
Securities-based lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	101,730	97,840
Current Fiscal Year	425	2,437
One Year Ago	2,384	1,132
Two Years Ago	1,017	655
Three Years Ago	621	132
Four Years Ago	100
Prior	249	245
Total	106,526	102,441
Other \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	647	639
Current Fiscal Year	7	199
One Year Ago	173	690
Two Years Ago	640	126
Three Years Ago	126	170
Four Years Ago	222
Prior	1,127	1,013
Total	2,942	2,837
Other \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	1,622	1,615
Current Fiscal Year	254	808
One Year Ago	684	180
Two Years Ago	225	981
Three Years Ago	956	1,260
Four Years Ago	1,156
Prior	2,719	2,862
Total	$ 7,616	$ 7,706

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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