Revenue from Contracts with Customers - Disaggregation of Revenues (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Servicing fees	$ 5,074	$ 5,421	$ 5,365
Management fees	1,771	1,851	1,616
Foreign exchange trading services	1,111	1,201	1,071
Securities finance	471	543	606
Software and processing fees	720	438	343
Total fee revenue	9,147	9,454	9,001
Net interest income	2,566	2,671	2,304
Total other income	43	6	(39)
Total revenue	11,756	12,131	11,266
Operating Segments | Investment Servicing
Disaggregation of Revenue [Line Items]
Topic 606 revenue	6,135	6,307
All other revenue	3,699	3,876
Servicing fees	5,074	5,429	5,365
Management fees	0	0	0
Foreign exchange trading services	974	1,071	999
Securities finance	462	543	606
Software and processing fees	691	443	336
Total fee revenue	7,201	7,486	7,306
Net interest income	2,590	2,691	2,309
Total other income	43	6	(39)
Total revenue	9,834	10,183	9,576
Operating Segments | Investment Servicing | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	5,074	5,429
All other revenue	0	0
Servicing fees	5,074	5,429
Operating Segments | Investment Servicing | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Management fees	0	0
Operating Segments | Investment Servicing | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	346	361
All other revenue	628	710
Foreign exchange trading services	974	1,071
Operating Segments | Investment Servicing | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	259	308
All other revenue	203	235
Securities finance	462	543
Operating Segments | Investment Servicing | Processing fees and other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	456	209
All other revenue	235	234
Software and processing fees	691	443
Operating Segments | Investment Servicing | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	6,135	6,307
All other revenue	1,066	1,179
Total fee revenue	7,201	7,486
Operating Segments | Investment Servicing | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	2,590	2,691
Net interest income	2,590	2,691
Operating Segments | Investment Servicing | Total other income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	43	6
Total other income	43	6
Operating Segments | Investment Management
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,908	1,981
All other revenue	14	(25)
Servicing fees	0	0	0
Management fees	1,771	1,851	1,616
Foreign exchange trading services	137	130	72
Securities finance	9	0	0
Software and processing fees	29	(5)	7
Total fee revenue	1,946	1,976	1,695
Net interest income	(24)	(20)	(5)
Total other income	0	0	0
Total revenue	1,922	1,956	1,690
Operating Segments | Investment Management | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Servicing fees	0	0
Operating Segments | Investment Management | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,771	1,851
All other revenue	0	0
Management fees	1,771	1,851
Operating Segments | Investment Management | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	137	130
All other revenue	0	0
Foreign exchange trading services	137	130
Operating Segments | Investment Management | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	9	0
Securities finance	9	0
Operating Segments | Investment Management | Processing fees and other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	29	(5)
Software and processing fees	29	(5)
Operating Segments | Investment Management | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,908	1,981
All other revenue	38	(5)
Total fee revenue	1,946	1,976
Operating Segments | Investment Management | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	(24)	(20)
Net interest income	(24)	(20)
Operating Segments | Investment Management | Total other income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Total other income	0	0
Other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	(8)
All other revenue	0	0
Servicing fees	0	(8)	0
Management fees	0	0	0
Foreign exchange trading services	0	0	0
Securities finance	0	0	0
Software and processing fees	0	0	0
Total fee revenue	0	(8)	0
Net interest income	0	0	0
Total other income	0	0	0
Total revenue	0	(8)	$ 0
Other | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	(8)
All other revenue	0	0
Servicing fees	0	(8)
Other | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Management fees	0	0
Other | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Foreign exchange trading services	0	0
Other | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Securities finance	0	0
Other | Processing fees and other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Software and processing fees	0	0
Other | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	(8)
All other revenue	0	0
Total fee revenue	0	(8)
Other | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Net interest income	0	0
Other | Total other income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0
All other revenue	0	0
Total other income	$ 0	$ 0