Loans - Schedule of Credit Quality Indicators for Term Loans by Origination Year (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Recorded Investment [Line Items]
Total	$ 184,829	$ 162,135
Percentage of total	100.00%	100.00%
All Classes except Consumer
Financing Receivable, Recorded Investment [Line Items]
Total	$ 150,434	$ 131,623
Corporate
Financing Receivable, Recorded Investment [Line Items]
Total	40,135	37,643
Financing receivable revolving converted to term loan	$ 725	$ 0
Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Percentage of total	42.00%	39.00%
Investment-Grade | All Classes except Consumer
Financing Receivable, Recorded Investment [Line Items]
Total	$ 63,971	$ 50,923
Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Percentage of total	53.00%	57.00%
Non-Investment- Grade | All Classes except Consumer
Financing Receivable, Recorded Investment [Line Items]
Total	$ 79,648	$ 75,179
Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Percentage of total	5.00%	4.00%
Other Metrics/ Unrated | All Classes except Consumer
Financing Receivable, Recorded Investment [Line Items]
Total	$ 6,815	$ 5,521
Corporate
Financing Receivable, Recorded Investment [Line Items]
Year one	6,651	9,775
Year two	5,942	3,733
Year three	3,279	3,944
Year four	2,988	4,061
Year five	2,670	2,168
More than five years	2,837	1,921
Revolving	12,455	9,061
Total	36,822	34,663
Corporate | Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	2,607	2,932
Year two	1,669	675
Year three	684	314
Year four	209	1,310
Year five	759	431
More than five years	508	273
Revolving	3,709	2,180
Total	10,145	8,115
Corporate | Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	4,042	6,843
Year two	4,273	3,051
Year three	2,595	3,630
Year four	2,779	2,751
Year five	1,911	1,737
More than five years	2,329	1,648
Revolving	8,746	6,806
Total	26,675	26,466
Corporate | Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Year one	2	0
Year two	0	7
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	75
Total	2	82
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Year one	4,707	5,032
Year two	4,231	2,613
Year three	2,147	1,992
Year four	1,747	1,332
Year five	681	1,385
More than five years	2,046	1,523
Revolving	10,663	10,390
Total	26,222	24,267
Commercial real estate | Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	734	799
Year two	744	532
Year three	407	444
Year four	335	478
Year five	212	760
More than five years	1,238	692
Revolving	1,281	1,883
Total	4,951	5,588
Commercial real estate | Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	3,971	4,139
Year two	3,487	2,081
Year three	1,740	1,548
Year four	1,412	854
Year five	469	625
More than five years	797	824
Revolving	9,382	8,507
Total	21,258	18,578
Commercial real estate | Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Year one	2	94
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	11	7
Revolving	0	0
Total	13	101
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Year one	3,633	5,125
Year two	3,508	938
Year three	103	182
Year four	106	261
Year five	198	217
More than five years	183	57
Revolving	10,792	11,609
Total	18,523	18,389
Residential real estate | Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	941	864
Year two	932	271
Year three	0	9
Year four	7	0
Year five	10	25
More than five years	31	0
Revolving	773	690
Total	2,694	1,859
Residential real estate | Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	1,385	2,744
Year two	1,219	564
Year three	14	0
Year four	0	96
Year five	50	73
More than five years	10	1
Revolving	10,019	10,919
Total	12,697	14,397
Residential real estate | Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Year one	1,307	1,517
Year two	1,357	103
Year three	89	173
Year four	99	165
Year five	138	119
More than five years	142	56
Revolving	0	0
Total	3,132	2,133
Securities-based
Financing Receivable, Recorded Investment [Line Items]
Year one	5
Year four		1
Year five	1	22
More than five years	291	264
Revolving	16,374	16,365
Total	16,671	16,652
Securities-based | Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	5
Year four		0
Year five	1	0
More than five years	0	264
Revolving	12,895	13,537
Total	12,901	13,801
Securities-based | Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	0
Year four		1
Year five	0	22
More than five years	291	0
Revolving	473	424
Total	764	447
Securities-based | Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Year one	0
Year four		0
Year five	0	0
More than five years	0	0
Revolving	3,006	2,404
Total	3,006	2,404
Other collateralized
Financing Receivable, Recorded Investment [Line Items]
Year one	5,420	6,496
Year two	4,583	3,024
Year three	2,608	726
Year four	614	775
Year five	659	428
More than five years	595	62
Revolving	35,994	24,405
Total	50,473	35,916
Other collateralized | Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	4,095	1,876
Year two	1,860	1,378
Year three	777	243
Year four	235	595
Year five	504	303
More than five years	294	15
Revolving	24,504	16,257
Total	32,269	20,667
Other collateralized | Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	1,212	4,316
Year two	2,577	1,598
Year three	1,795	464
Year four	367	180
Year five	149	125
More than five years	301	47
Revolving	11,488	8,148
Total	17,889	14,878
Other collateralized | Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Year one	113	304
Year two	146	48
Year three	36	19
Year four	12	0
Year five	6	0
More than five years	0	0
Revolving	2	0
Total	315	371
Other
Financing Receivable, Recorded Investment [Line Items]
Year one	149	368
Year two	179	390
Year three	291	50
Year four	10
Year five		8
More than five years	5
Revolving	1,089	920
Total	1,723	1,736
Other | Investment-Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	44	68
Year two	17	0
Year three	0	30
Year four	0
Year five		0
More than five years	0
Revolving	950	795
Total	1,011	893
Other | Non-Investment- Grade
Financing Receivable, Recorded Investment [Line Items]
Year one	105	290
Year two	162	60
Year three	29	20
Year four	10
Year five		0
More than five years	0
Revolving	59	43
Total	365	413
Other | Other Metrics/ Unrated
Financing Receivable, Recorded Investment [Line Items]
Year one	0	10
Year two	0	330
Year three	262	0
Year four	0
Year five		8
More than five years	5
Revolving	80	82
Total	$ 347	$ 430