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, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 214,139	$ 204,554
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	6,389	6,213
Current Fiscal Year	58	88
One Year Ago	50	166
Two Years Ago	59	104
Three Years Ago	90	54
Four Years Ago	35
Prior	83	133
Total	6,764	6,758
Corporate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	2,133	2,350
Current Fiscal Year	52	0
One Year Ago	0	0
Two Years Ago	0	15
Three Years Ago	15	29
Four Years Ago	9
Prior	83	0
Total	2,292	2,394
Corporate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	4,256	3,863
Current Fiscal Year	6	88
One Year Ago	50	166
Two Years Ago	59	89
Three Years Ago	75	25
Four Years Ago	26
Prior	0	133
Total	4,472	4,364
Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	34,304	31,734
Current Fiscal Year	3,739	2,994
One Year Ago	2,866	2,782
Two Years Ago	2,594	365
Three Years Ago	323	80
Four Years Ago	0
Prior	1,043	1,543
Total	44,869	39,498
Secured lending facilities \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	9,271	9,494
Current Fiscal Year	463	1,535
One Year Ago	1,489	392
Two Years Ago	293	0
Three Years Ago	0	0
Four Years Ago	0
Prior	60	356
Total	11,576	11,777
Secured lending facilities \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	25,033	22,240
Current Fiscal Year	3,276	1,459
One Year Ago	1,377	2,390
Two Years Ago	2,301	365
Three Years Ago	323	80
Four Years Ago	0
Prior	983	1,187
Total	33,293	27,721
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	172	170
Current Fiscal Year	1,333	1,328
One Year Ago	1,314	2,184
Two Years Ago	2,127	1,864
Three Years Ago	1,850	756
Four Years Ago	747
Prior	1,261	2,376
Total	8,804	8,678
Commercial real estate \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	0	261
One Year Ago	364	284
Two Years Ago	383	370
Three Years Ago	296	0
Four Years Ago	0
Prior	0	195
Total	1,043	1,110
Commercial real estate \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	172	170
Current Fiscal Year	1,333	1,067
One Year Ago	950	1,900
Two Years Ago	1,744	1,494
Three Years Ago	1,554	756
Four Years Ago	747
Prior	1,261	2,181
Total	7,761	7,568
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	157	149
Current Fiscal Year	4,820	9,137
One Year Ago	8,771	13,740
Two Years Ago	13,364	13,690
Three Years Ago	13,355	8,450
Four Years Ago	8,173
Prior	14,521	15,209
Total	63,161	60,375
Residential real estate \| Less than or equal to 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	157	149
Current Fiscal Year	4,379	8,168
One Year Ago	7,845	12,650
Two Years Ago	12,311	12,763
Three Years Ago	12,444	8,017
Four Years Ago	7,752
Prior	13,466	14,106
Total	58,354	55,853
Residential real estate \| Greater than 80%
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	0	0
Current Fiscal Year	441	969
One Year Ago	926	1,090
Two Years Ago	1,053	927
Three Years Ago	911	433
Four Years Ago	421
Prior	1,055	1,103
Total	4,807	4,522
Residential real estate \| Greater than or equal to 740
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	117	108
Current Fiscal Year	4,024	7,390
One Year Ago	7,089	10,927
Two Years Ago	10,612	11,075
Three Years Ago	10,807	6,916
Four Years Ago	6,691
Prior	11,106	11,642
Total	50,446	48,058
Residential real estate \| 680-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	35	33
Current Fiscal Year	724	1,517
One Year Ago	1,468	2,424
Two Years Ago	2,372	2,376
Three Years Ago	2,314	1,430
Four Years Ago	1,382
Prior	3,004	3,131
Total	11,299	10,911
Residential real estate \| Less than or equal to 679
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	5	8
Current Fiscal Year	72	230
One Year Ago	214	389
Two Years Ago	380	239
Three Years Ago	234	104
Four Years Ago	100
Prior	411	436
Total	1,416	1,406
Securities-based lending and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	79,255	78,066
Current Fiscal Year	956	2,585
One Year Ago	2,235	2,748
Two Years Ago	2,551	872
Three Years Ago	757	849
Four Years Ago	782
Prior	4,005	4,125
Total	90,541	89,245
Securities-based lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	71,825	71,474
Current Fiscal Year	403	1,612
One Year Ago	1,214	1,128
Two Years Ago	924	165
Three Years Ago	100	0
Four Years Ago	39
Prior	225	215
Total	74,730	74,594
Other \| Investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	5,814	5,230
Current Fiscal Year	221	627
One Year Ago	635	816
Two Years Ago	443	330
Three Years Ago	166	435
Four Years Ago	280
Prior	1,352	2,096
Total	8,911	9,534
Other \| Non-investment grade
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving	1,616	1,362
Current Fiscal Year	332	346
One Year Ago	386	804
Two Years Ago	1,184	377
Three Years Ago	491	414
Four Years Ago	463
Prior	2,428	1,814
Total	$ 6,900	$ 5,117

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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