Loans - Wholesale Loan Portfolio, Internal Risk Ratings (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	$ 1,280,870	$ 1,089,598	$ 1,010,206
Loans by origination year
Total retained loans	1,280,870	1,089,598	1,010,206
Gross charge-offs by origination year
Total gross charge-offs	7,653	4,326	4,564
Wholesale
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	$ 672,472	$ 603,670	560,354
% of investment-grade to total retained loans	68.23%	70.47%
% of total criticized to total retained loans	3.51%	2.60%
% of criticized nonaccrual to total retained loans	0.35%	0.33%
Loans by origination year
Total retained loans	$ 672,472	$ 603,670	560,354
Gross charge-offs by origination year
Total gross charge-offs	1,011	322	$ 283
Wholesale | First Republic
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	53,900
Loans by origination year
Total retained loans	53,900
Wholesale | Investment-grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	458,838	425,412
Loans by origination year
Total retained loans	458,838	425,412
Wholesale | Total noninvestment- grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	213,634	178,258
Loans by origination year
Total retained loans	213,634	178,258
Wholesale | Noncriticized
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	190,056	162,553
Loans by origination year
Total retained loans	190,056	162,553
Wholesale | Criticized performing
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	21,232	13,742
Loans by origination year
Total retained loans	21,232	13,742
Wholesale | Criticized nonaccrual
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	2,346	1,963
Loans by origination year
Total retained loans	2,346	1,963
Wholesale | Secured by real estate
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	$ 162,338	$ 126,732
% of investment-grade to total retained loans	74.17%	78.55%
% of total criticized to total retained loans	4.74%	3.08%
% of criticized nonaccrual to total retained loans	0.25%	0.19%
Loans by origination year
Term loans originated in 2023/2022	$ 15,164	$ 30,206
Term loans originated in 2022/2021	41,453	28,009
Term loans originated in 2021/2020	33,623	17,805
Term loans originated in 2020/2019	20,660	18,164
Term loans originated in 2019/2018	19,664	7,672
Term loans originated prior to 2019/2018	29,026	22,948
Revolving loans within revolving period	2,746	1,926
Revolving loans converted to term loans	2	2
Total retained loans	162,338	126,732
Gross charge-offs by origination year
Gross charge-offs originated in 2023	20
Gross charge-offs originated in 2022	48
Gross charge-offs originated in 2021	22
Gross charge-offs originated in 2020	0
Gross charge-offs originated in 2019	23
Gross charge-offs originated prior to 2019	78
Gross charge-offs originated within the revolving period	0
Gross charge-offs originated converted to term loans	1
Total gross charge-offs	192
Wholesale | Secured by real estate | First Republic
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	33,800
Loans by origination year
Term loans originated in 2023/2022	3,300
Term loans originated in 2022/2021	11,200
Term loans originated in 2021/2020	6,200
Term loans originated in 2020/2019	4,300
Term loans originated in 2019/2018	2,900
Term loans originated prior to 2019/2018	5,100
Revolving loans within revolving period	838
Total retained loans	33,800
Wholesale | Secured by real estate | Investment-grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	120,405	99,552
Loans by origination year
Term loans originated in 2023/2022	10,687	24,134
Term loans originated in 2022/2021	28,874	22,407
Term loans originated in 2021/2020	25,784	14,773
Term loans originated in 2020/2019	16,820	14,666
Term loans originated in 2019/2018	15,677	5,277
Term loans originated prior to 2019/2018	21,108	17,289
Revolving loans within revolving period	1,455	1,006
Revolving loans converted to term loans	0	0
Total retained loans	120,405	99,552
Wholesale | Secured by real estate | Total noninvestment- grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	41,933	27,180
Loans by origination year
Term loans originated in 2023/2022	4,477	6,072
Term loans originated in 2022/2021	12,579	5,602
Term loans originated in 2021/2020	7,839	3,032
Term loans originated in 2020/2019	3,840	3,498
Term loans originated in 2019/2018	3,987	2,395
Term loans originated prior to 2019/2018	7,918	5,659
Revolving loans within revolving period	1,291	920
Revolving loans converted to term loans	2	2
Total retained loans	41,933	27,180
Wholesale | Secured by real estate | Noncriticized
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	34,241	23,272
Loans by origination year
Total retained loans	34,241	23,272
Wholesale | Secured by real estate | Criticized performing
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	7,291	3,662
Loans by origination year
Total retained loans	7,291	3,662
Wholesale | Secured by real estate | Criticized nonaccrual
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	$ 401	$ 246
% of criticized nonaccrual to total retained loans	0.25%	0.19%
Loans by origination year
Total retained loans	$ 401	$ 246
Wholesale | Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	$ 167,166	$ 167,660
% of investment-grade to total retained loans	43.44%	45.49%
% of total criticized to total retained loans	8.32%	5.96%
% of criticized nonaccrual to total retained loans	0.73%	0.61%
Loans by origination year
Term loans originated in 2023/2022	$ 33,765	$ 45,160
Term loans originated in 2022/2021	27,086	20,782
Term loans originated in 2021/2020	13,575	6,504
Term loans originated in 2020/2019	4,280	4,501
Term loans originated in 2019/2018	2,174	1,273
Term loans originated prior to 2019/2018	2,121	2,003
Revolving loans within revolving period	84,090	87,354
Revolving loans converted to term loans	75	83
Total retained loans	167,166	167,660
Gross charge-offs by origination year
Gross charge-offs originated in 2023	25
Gross charge-offs originated in 2022	8
Gross charge-offs originated in 2021	110
Gross charge-offs originated in 2020	55
Gross charge-offs originated in 2019	2
Gross charge-offs originated prior to 2019	12
Gross charge-offs originated within the revolving period	259
Gross charge-offs originated converted to term loans	8
Total gross charge-offs	479
Wholesale | Commercial and industrial | First Republic
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	3,000
Loans by origination year
Term loans originated in 2023/2022	364
Term loans originated in 2022/2021	568
Term loans originated in 2021/2020	471
Term loans originated in 2020/2019	212
Term loans originated in 2019/2018	53
Term loans originated prior to 2019/2018	121
Revolving loans within revolving period	1,200
Revolving loans converted to term loans	12
Total retained loans	3,000
Wholesale | Commercial and industrial | Investment-grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	72,624	76,275
Loans by origination year
Term loans originated in 2023/2022	14,875	21,072
Term loans originated in 2022/2021	10,642	8,338
Term loans originated in 2021/2020	4,276	3,045
Term loans originated in 2020/2019	2,291	1,995
Term loans originated in 2019/2018	1,030	748
Term loans originated prior to 2019/2018	1,115	989
Revolving loans within revolving period	38,394	40,087
Revolving loans converted to term loans	1	1
Total retained loans	72,624	76,275
Wholesale | Commercial and industrial | Total noninvestment- grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	94,542	91,385
Loans by origination year
Term loans originated in 2023/2022	18,890	24,088
Term loans originated in 2022/2021	16,444	12,444
Term loans originated in 2021/2020	9,299	3,459
Term loans originated in 2020/2019	1,989	2,506
Term loans originated in 2019/2018	1,144	525
Term loans originated prior to 2019/2018	1,006	1,014
Revolving loans within revolving period	45,696	47,267
Revolving loans converted to term loans	74	82
Total retained loans	94,542	91,385
Wholesale | Commercial and industrial | Noncriticized
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	80,637	81,393
Loans by origination year
Total retained loans	80,637	81,393
Wholesale | Commercial and industrial | Criticized performing
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	12,684	8,974
Loans by origination year
Total retained loans	12,684	8,974
Wholesale | Commercial and industrial | Criticized nonaccrual
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	1,221	1,018
Loans by origination year
Total retained loans	1,221	1,018
Wholesale | Other
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	$ 342,968	$ 309,278
% of investment-grade to total retained loans	77.50%	80.70%
% of total criticized to total retained loans	0.58%	0.58%
% of criticized nonaccrual to total retained loans	0.21%	0.23%
Loans by origination year
Term loans originated in 2023/2022	$ 52,392	$ 48,950
Term loans originated in 2022/2021	26,126	22,960
Term loans originated in 2021/2020	16,202	14,836
Term loans originated in 2020/2019	12,271	5,228
Term loans originated in 2019/2018	4,532	2,610
Term loans originated prior to 2019/2018	8,663	7,726
Revolving loans within revolving period	220,529	203,289
Revolving loans converted to term loans	2,253	3,679
Total retained loans	342,968	309,278
Gross charge-offs by origination year
Gross charge-offs originated in 2023	5
Gross charge-offs originated in 2022	298
Gross charge-offs originated in 2021	8
Gross charge-offs originated in 2020	8
Gross charge-offs originated in 2019	0
Gross charge-offs originated prior to 2019	8
Gross charge-offs originated within the revolving period	13
Gross charge-offs originated converted to term loans	0
Total gross charge-offs	340
Wholesale | Other | Individuals and individual entities
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	106,900
Loans by origination year
Total retained loans	106,900
Wholesale | Other | SPEs
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	91,200
Loans by origination year
Total retained loans	91,200
Wholesale | Other | Financial institutions
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	87,500
Loans by origination year
Total retained loans	87,500
Wholesale | Other | First Republic
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	17,100
Loans by origination year
Term loans originated in 2023/2022	610
Term loans originated in 2022/2021	1,000
Term loans originated in 2021/2020	820
Term loans originated in 2020/2019	1,100
Term loans originated in 2019/2018	244
Term loans originated prior to 2019/2018	1,400
Revolving loans within revolving period	11,800
Revolving loans converted to term loans	56
Total retained loans	17,100
Wholesale | Other | Investment-grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	265,809	249,585
Loans by origination year
Term loans originated in 2023/2022	38,338	32,121
Term loans originated in 2022/2021	18,034	15,864
Term loans originated in 2021/2020	10,033	13,015
Term loans originated in 2020/2019	10,099	4,529
Term loans originated in 2019/2018	3,721	2,159
Term loans originated prior to 2019/2018	6,662	7,251
Revolving loans within revolving period	176,728	171,049
Revolving loans converted to term loans	2,194	3,597
Total retained loans	265,809	249,585
Wholesale | Other | Total noninvestment- grade
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	77,159	59,693
Loans by origination year
Term loans originated in 2023/2022	14,054	16,829
Term loans originated in 2022/2021	8,092	7,096
Term loans originated in 2021/2020	6,169	1,821
Term loans originated in 2020/2019	2,172	699
Term loans originated in 2019/2018	811	451
Term loans originated prior to 2019/2018	2,001	475
Revolving loans within revolving period	43,801	32,240
Revolving loans converted to term loans	59	82
Total retained loans	77,159	59,693
Wholesale | Other | Noncriticized
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	75,178	57,888
Loans by origination year
Total retained loans	75,178	57,888
Wholesale | Other | Criticized performing
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	1,257	1,106
Loans by origination year
Total retained loans	1,257	1,106
Wholesale | Other | Criticized nonaccrual
Loans and Leases Receivable Disclosure [Line Items]
Retained loans	724	699
Loans by origination year
Total retained loans	$ 724	$ 699