Revenue from Contracts with Customers - Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Servicing fees	$ 1,272	$ 1,333	$ 3,775	$ 4,135
Management fees	445	474	1,306	1,411
Foreign exchange trading services	284	288	837	907
Securities finance	116	128	360	423
Processing fees and other	142	95	501	252
Total fee revenue	2,259	2,318	6,779	7,128
Net interest income	644	672	1,930	1,974
Gains (losses) related to investment securities, net	0	(1)	(1)	6
Total revenue	2,903	2,989	8,708	9,108
Operating Segments \| Investment Servicing
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,523	1,522	4,559	4,719
All other revenue	901	960	2,737	2,889
Servicing fees	1,272	1,333	3,775	4,135
Management fees	0	0	0	0
Foreign exchange trading services	249	255	735	810
Securities finance	114	128	353	423
Processing fees and other	140	87	483	243
Total fee revenue	1,775	1,803	5,346	5,611
Net interest income	649	680	1,951	1,991
Gains (losses) related to investment securities, net	0	(1)	(1)	6
Total revenue	2,424	2,482	7,296	7,608
Operating Segments \| Investment Servicing \| Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,272	1,333	3,775	4,135
All other revenue	0	0	0	0
Servicing fees	1,272	1,333	3,775	4,135
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	90	89	258	275
All other revenue	159	166	477	535
Foreign exchange trading services	249	255	735	810
Operating Segments \| Investment Servicing \| Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	64	73	209	240
All other revenue	50	55	144	183
Securities finance	114	128	353	423
Operating Segments \| Investment Servicing \| Processing fees and other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	97	27	317	69
All other revenue	43	60	166	174
Processing fees and other	140	87	483	243
Operating Segments \| Investment Servicing \| Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	1,523	1,522	4,559	4,719
All other revenue	252	281	787	892
Total fee revenue	1,775	1,803	5,346	5,611
Operating Segments \| Investment Servicing \| Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	649	680	1,951	1,991
Net interest income	649	680	1,951	1,991
Operating Segments \| Investment Servicing \| Gains (losses) related to investment securities, net
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	0	(1)	(1)	6
Gains (losses) related to investment securities, net	0	(1)	(1)	6
Operating Segments \| Investment Management
Disaggregation of Revenue [Line Items]
Topic 606 revenue	480	507	1,408	1,508
All other revenue	(1)	0	4	(8)
Servicing fees	0	0	0	0
Management fees	445	474	1,306	1,411
Foreign exchange trading services	35	33	102	97
Securities finance	2	0	7	0
Processing fees and other	2	8	18	9
Total fee revenue	484	515	1,433	1,517
Net interest income	(5)	(8)	(21)	(17)
Gains (losses) related to investment securities, net	0	0	0	0
Total revenue	479	507	1,412	1,500
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	445	474	1,306	1,411
All other revenue	0	0	0	0
Management fees	445	474	1,306	1,411
Operating Segments \| Investment Management \| Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	35	33	102	97
All other revenue	0	0	0	0
Foreign exchange trading services	35	33	102	97
Operating Segments \| Investment Management \| Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	2	0	7	0
Securities finance	2	0	7	0
Operating Segments \| Investment Management \| Processing fees and other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	2	8	18	9
Processing fees and other	2	8	18	9
Operating Segments \| Investment Management \| Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	480	507	1,408	1,508
All other revenue	4	8	25	9
Total fee revenue	484	515	1,433	1,517
Operating Segments \| Investment Management \| Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	(5)	(8)	(21)	(17)
Net interest income	(5)	(8)	(21)	(17)
Operating Segments \| Investment Management \| Gains (losses) related to investment securities, net
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0	0
All other revenue	0	0	0	0
Gains (losses) related to investment securities, net	0	0	0	0
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
Processing fees and other	0	0	0	0
Total fee revenue	0	0	0	0
Net interest income	0	0	0	0
Gains (losses) related to investment securities, net	0	0	0	0
Total revenue	$ 0	$ 0	$ 0	$ 0

Fees And Commissions, Foreign Exchange Trading Services

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The net amount of operating interest income (expense).

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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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