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	Sep. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 257,080	$ 226,900
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	7,482	6,631
Current Fiscal Year	163	134
One Year Ago	129	50
Two Years Ago	49	25
Three Years Ago	0	15
Four Years Ago	15
Prior	1	34
Total	7,839	6,889
Corporate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	2,606	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	2,825	2,790
Corporate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	4,876	3,963
Current Fiscal Year	38	58
One Year Ago	50	50
Two Years Ago	49	25
Three Years Ago	0	0
Four Years Ago	0
Prior	1	3
Total	5,014	4,099
Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	49,458	39,158
Current Fiscal Year	7,398	3,681
One Year Ago	3,246	2,730
Two Years Ago	1,602	2,188
Three Years Ago	1,106	198
Four Years Ago	12
Prior	788	887
Total	63,610	48,842
Secured lending facilities \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	14,662	11,405
Current Fiscal Year	988	818
One Year Ago	268	1,371
Two Years Ago	555	279
Three Years Ago	115	0
Four Years Ago	0
Prior	0	100
Total	16,588	13,973
Secured lending facilities \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	34,796	27,753
Current Fiscal Year	6,410	2,863
One Year Ago	2,978	1,359
Two Years Ago	1,047	1,909
Three Years Ago	991	198
Four Years Ago	12
Prior	788	787
Total	47,022	34,869
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	19	161
Current Fiscal Year	1,608	2,349
One Year Ago	2,022	1,123
Two Years Ago	683	1,793
Three Years Ago	1,499	1,769
Four Years Ago	1,319
Prior	703	1,217
Total	7,853	8,412
Commercial real estate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	11	0
Current Fiscal Year	330	147
One Year Ago	582	351
Two Years Ago	265	305
Three Years Ago	263	166
Four Years Ago	251
Prior	37	0
Total	1,739	969
Commercial real estate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	8	161
Current Fiscal Year	1,278	2,202
One Year Ago	1,440	772
Two Years Ago	418	1,488
Three Years Ago	1,236	1,603
Four Years Ago	1,068
Prior	666	1,217
Total	6,114	7,443
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	203	180
Current Fiscal Year	8,109	10,451
One Year Ago	9,773	8,410
Two Years Ago	7,808	12,962
Three Years Ago	12,339	12,985
Four Years Ago	12,410
Prior	20,268	21,750
Total	70,910	66,738
Residential real estate \| Less than or equal to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	203	180
Current Fiscal Year	7,318	9,458
One Year Ago	8,838	7,529
Two Years Ago	6,973	11,941
Three Years Ago	11,378	12,094
Four Years Ago	11,558
Prior	18,974	20,355
Total	65,242	61,557
Residential real estate \| Greater than 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	791	993
One Year Ago	935	881
Two Years Ago	835	1,021
Three Years Ago	961	891
Four Years Ago	852
Prior	1,294	1,395
Total	5,668	5,181
Residential real estate \| Greater than or equal to 740
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	159	136
Current Fiscal Year	6,748	8,653
One Year Ago	8,057	6,778
Two Years Ago	6,270	10,294
Three Years Ago	9,804	10,510
Four Years Ago	10,053
Prior	15,975	17,088
Total	57,066	53,459
Residential real estate \| 680-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	38	39
Current Fiscal Year	1,210	1,607
One Year Ago	1,530	1,431
Two Years Ago	1,344	2,298
Three Years Ago	2,176	2,247
Four Years Ago	2,143
Prior	3,835	4,171
Total	12,276	11,793
Residential real estate \| Less than or equal to 679
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	6	5
Current Fiscal Year	151	191
One Year Ago	186	201
Two Years Ago	194	370
Three Years Ago	359	228
Four Years Ago	214
Prior	458	491
Total	1,568	1,486
Securities-based lending and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	94,132	84,325
Current Fiscal Year	2,103	2,463
One Year Ago	2,314	2,058
Two Years Ago	2,017	1,974
Three Years Ago	1,686	652
Four Years Ago	530
Prior	4,086	4,547
Total	106,868	96,019
Securities-based lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	86,581	76,432
Current Fiscal Year	1,017	1,291
One Year Ago	1,358	949
Two Years Ago	812	449
Three Years Ago	238	100
Four Years Ago	100
Prior	238	270
Total	90,344	79,491
Other \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	5,995	6,342
Current Fiscal Year	286	719
One Year Ago	780	424
Two Years Ago	305	472
Three Years Ago	183	14
Four Years Ago	18
Prior	1,100	1,430
Total	8,667	9,401
Other \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	1,556	1,551
Current Fiscal Year	800	453
One Year Ago	176	685
Two Years Ago	900	1,053
Three Years Ago	1,265	538
Four Years Ago	412
Prior	2,748	2,847
Total	$ 7,857	$ 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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