Revenue from Contracts with Customers - Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregation of Revenue [Line Items]
Servicing fees	$ 1,239	$ 1,259	$ 2,467	$ 2,476
Management fees	511	461	1,021	918
Foreign exchange trading services	336	303	667	645
Securities finance	108	117	204	226
Software and processing fees	214	221	421	386
Other fee revenue	48	58	98	103
Total fee revenue	2,456	2,419	4,878	4,754
Net interest income	735	691	1,451	1,457
Total other income			0	0
Total revenue	3,191	3,110	6,329	6,211
Operating Segments | Investment Servicing
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,542	1,580	3,069	3,070
All other revenue	1,082	1,027	2,142	2,133
Servicing fees	1,239	1,259	2,467	2,476
Management fees	0	0	0	0
Foreign exchange trading services	304	276	612	597
Securities finance	101	109	191	212
Software and processing fees	214	221	421	386
Other fee revenue	36	55	79	83
Total fee revenue	1,894	1,920	3,770	3,754
Net interest income	730	687	1,441	1,449
Total other income			0	0
Total revenue	2,624	2,607	5,211	5,203
Operating Segments | Investment Servicing | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,239	1,259	2,467	2,476
All other revenue	0	0	0	0
Servicing fees	1,239	1,259	2,467	2,476
Operating Segments | Investment Servicing | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	0	0	0	0
Management fees	0	0	0	0
Operating Segments | Investment Servicing | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	95	86	190	176
All other revenue	209	190	422	421
Foreign exchange trading services	304	276	612	597
Operating Segments | Investment Servicing | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	46	61	94	124
All other revenue	55	48	97	88
Securities finance	101	109	191	212
Operating Segments | Investment Servicing | Software and processing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	162	174	318	294
All other revenue	52	47	103	92
Software and processing fees	214	221	421	386
Operating Segments | Investment Servicing | Other fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	36	55	79	83
Other fee revenue	36	55	79	83
Operating Segments | Investment Servicing | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,542	1,580	3,069	3,070
All other revenue	352	340	701	684
Total fee revenue	1,894	1,920	3,770	3,754
Operating Segments | Investment Servicing | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	730	687	1,441	1,449
Net interest income	730	687	1,441	1,449
Operating Segments | Investment Management
Disaggregation of Revenue [Line Items]
Topic 606 revenue	543	488	1,076	966
All other revenue	24	15	42	42
Servicing fees	0	0	0	0
Management fees	511	461	1,021	918
Foreign exchange trading services	32	27	55	48
Securities finance	7	8	13	14
Software and processing fees	0	0	0	0
Other fee revenue	12	3	19	20
Total fee revenue	562	499	1,108	1,000
Net interest income	5	4	10	8
Total other income			0	0
Total revenue	567	503	1,118	1,008
Operating Segments | Investment Management | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	0	0	0	0
Servicing fees	0	0	0	0
Operating Segments | Investment Management | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	511	461	1,021	918
All other revenue	0	0	0	0
Management fees	511	461	1,021	918
Operating Segments | Investment Management | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	32	27	55	48
All other revenue	0	0	0	0
Foreign exchange trading services	32	27	55	48
Operating Segments | Investment Management | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	7	8	13	14
Securities finance	7	8	13	14
Operating Segments | Investment Management | Software and processing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	0	0	0	0
Software and processing fees	0	0	0	0
Operating Segments | Investment Management | Other fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	12	3	19	20
Other fee revenue	12	3	19	20
Operating Segments | Investment Management | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	543	488	1,076	966
All other revenue	19	11	32	34
Total fee revenue	562	499	1,108	1,000
Operating Segments | Investment Management | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	5	4	10	8
Net interest income	5	4	10	8
Other
Disaggregation of Revenue [Line Items]
Servicing fees	0	0	0	0
Management fees	0	0	0	0
Foreign exchange trading services	0	0	0	0
Securities finance	0	0	0	0
Software and processing fees	0	0	0	0
Other fee revenue	0	0	0	0
Total fee revenue	0	0	0	0
Net interest income	0	0	0	0
Total other income			0	0
Total revenue	$ 0	$ 0	$ 0	$ 0