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	Jun. 30, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 290,566	$ 269,852
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	8,678	6,942
Current Fiscal Year	75	165
One Year Ago	35	129
Two Years Ago	128	25
Three Years Ago	24	0
Four Years Ago	0
Prior	15	16
Total	8,955	7,277
Corporate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	3,070	2,362
Current Fiscal Year	0	125
One Year Ago	0	79
Two Years Ago	78	0
Three Years Ago	0	0
Four Years Ago	0
Prior	15	15
Total	3,163	2,581
Corporate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	5,608	4,580
Current Fiscal Year	75	40
One Year Ago	35	50
Two Years Ago	50	25
Three Years Ago	24	0
Four Years Ago	0
Prior	0	1
Total	5,792	4,696
Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	56,810	53,624
Current Fiscal Year	4,665	9,762
One Year Ago	8,799	2,698
Two Years Ago	1,302	1,531
Three Years Ago	856	970
Four Years Ago	615
Prior	490	564
Total	73,537	69,149
Secured lending facilities \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	18,601	15,709
Current Fiscal Year	999	2,514
One Year Ago	1,528	78
Two Years Ago	48	596
Three Years Ago	266	13
Four Years Ago	5
Prior	9	7
Total	21,456	18,917
Secured lending facilities \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	38,209	37,915
Current Fiscal Year	3,666	7,248
One Year Ago	7,271	2,620
Two Years Ago	1,254	935
Three Years Ago	590	957
Four Years Ago	610
Prior	481	557
Total	52,081	50,232
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	19	34
Current Fiscal Year	976	2,425
One Year Ago	2,170	1,962
Two Years Ago	1,914	562
Three Years Ago	547	1,426
Four Years Ago	1,061
Prior	1,191	1,630
Total	7,878	8,039
Commercial real estate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	19	34
Current Fiscal Year	0	322
One Year Ago	634	577
Two Years Ago	540	153
Three Years Ago	153	332
Four Years Ago	166
Prior	28	37
Total	1,540	1,455
Commercial real estate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	976	2,103
One Year Ago	1,536	1,385
Two Years Ago	1,374	409
Three Years Ago	394	1,094
Four Years Ago	895
Prior	1,163	1,593
Total	6,338	6,584
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	238	219
Current Fiscal Year	6,555	10,951
One Year Ago	10,453	9,489
Two Years Ago	8,859	7,601
Three Years Ago	7,134	12,106
Four Years Ago	11,614
Prior	30,774	32,037
Total	75,627	72,403
Residential real estate \| Less than or equal to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	238	219
Current Fiscal Year	5,993	9,900
One Year Ago	9,445	8,571
Two Years Ago	8,006	6,788
Three Years Ago	6,369	11,159
Four Years Ago	10,712
Prior	28,779	29,944
Total	69,542	66,581
Residential real estate \| Greater than 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	562	1,051
One Year Ago	1,008	918
Two Years Ago	853	813
Three Years Ago	765	947
Four Years Ago	902
Prior	1,995	2,093
Total	6,085	5,822
Residential real estate \| Greater than or equal to 740
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	184	172
Current Fiscal Year	5,453	9,096
One Year Ago	8,650	7,825
Two Years Ago	7,299	6,099
Three Years Ago	5,711	9,613
Four Years Ago	9,217
Prior	24,596	25,543
Total	61,110	58,348
Residential real estate \| 680-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	47	40
Current Fiscal Year	948	1,666
One Year Ago	1,622	1,480
Two Years Ago	1,389	1,315
Three Years Ago	1,241	2,138
Four Years Ago	2,056
Prior	5,554	5,841
Total	12,857	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	154	189
One Year Ago	181	184
Two Years Ago	171	187
Three Years Ago	182	355
Four Years Ago	341
Prior	624	653
Total	1,660	1,575
Securities-based lending and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	111,160	100,094
Current Fiscal Year	2,256	3,444
One Year Ago	2,883	2,002
Two Years Ago	1,386	1,762
Three Years Ago	1,556	1,562
Four Years Ago	1,361
Prior	3,967	4,120
Total	124,569	112,984
Securities-based lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	108,745	97,840
Current Fiscal Year	1,264	2,437
One Year Ago	2,128	1,132
Two Years Ago	532	655
Three Years Ago	529	132
Four Years Ago	67
Prior	232	245
Total	113,497	102,441
Other \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	721	639
Current Fiscal Year	6	199
One Year Ago	195	690
Two Years Ago	640	126
Three Years Ago	140	170
Four Years Ago	222
Prior	1,010	1,013
Total	2,934	2,837
Other \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	1,694	1,615
Current Fiscal Year	986	808
One Year Ago	560	180
Two Years Ago	214	981
Three Years Ago	887	1,260
Four Years Ago	1,072
Prior	2,725	2,862
Total	$ 8,138	$ 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.

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