Line of Business Information - Summary of Line of Business (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Servicing fees	$ 1,339	$ 1,239	$ 2,635	$ 2,481
Management fees	397	293	779	563
Trading services	289	267	564	539
Securities finance	179	156	312	290
Processing fees and other	31	98	143	150
Total fee revenue	2,235	2,053	4,433	4,023
Net interest income	575	521	1,085	1,033
Gains (losses) related to investment securities, net	0	(1)	(40)	1
Total revenue	2,810	2,573	5,478	5,057
Provision for loan losses	3	4	1	8
Total expenses	2,031	1,860	4,117	3,910
Income before income tax expense	$ 776	$ 709	$ 1,360	$ 1,139
Pre-tax margin	28.00%	28.00%	25.00%	23.00%
Operating Segments \| Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,339	$ 1,239	$ 2,635	$ 2,481
Management fees	0	0	0	0
Trading services	272	254	529	512
Securities finance	179	156	312	290
Processing fees and other	32	103	138	152
Total fee revenue	1,822	1,752	3,614	3,435
Net interest income	576	520	1,085	1,032
Gains (losses) related to investment securities, net	0	(1)	(40)	1
Total revenue	2,398	2,271	4,659	4,468
Provision for loan losses	3	4	1	8
Total expenses	1,649	1,599	3,377	3,286
Income before income tax expense	$ 746	$ 668	$ 1,281	$ 1,174
Pre-tax margin	31.00%	29.00%	27.00%	26.00%
Operating Segments \| Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0	$ 0
Management fees	397	293	779	563
Trading services	17	13	35	27
Securities finance	0	0	0	0
Processing fees and other	(1)	(5)	5	(2)
Total fee revenue	413	301	819	588
Net interest income	(1)	1	0	1
Gains (losses) related to investment securities, net	0	0	0	0
Total revenue	412	302	819	589
Provision for loan losses	0	0	0	0
Total expenses	311	244	640	500
Income before income tax expense	$ 101	$ 58	$ 179	$ 89
Pre-tax margin	25.00%	19.00%	22.00%	15.00%
Other
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0	$ 0
Management fees	0	0	0	0
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
Provision for loan losses	0	0	0	0
Total expenses	71	17	100	124
Income before income tax expense	$ (71)	$ (17)	$ (100)	$ (124)

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Trading Services Revenue

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Amount of fees and commissions from financial services and banking activities and correspondent clearing. Includes fees from depositor accounts, credit cards, merchant discounts, and fiduciary and trust activities, guarantee fees, investment advisory, management, and administrative fees, transfer agent fees, and insurance commissions.

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Income from services rendered by trust departments or by any consolidated subsidiaries acting in a fiduciary capacity, including fees earned for (1) acting as an agent for fiduciary placement and loans and (2) custody or investment advisory services when such fees are not separately billed to the customer. This item excludes commissions and fees received for the accumulation or disbursement of funds deposited to Individual Retirement or Keogh plan accounts when such are not handled by the reporting entity's trust department.

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Amount of fee and commission revenue classified as other.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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-Publisher FASB
-Name Accounting Standards Codification
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The net amount of operating interest income (expense).

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Amount of revenue from providing investment advisory, asset management and administrative services, including, but not limited to, distribution and shareholder services, accounting, tax, legal, regulatory filing, share registration, and shareholder correspondence activities.

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Amount of fees and commissions from banking, advisory, brokerage, and securities underwriting activities. Activities include, but are not limited to, underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, sale and servicing of mutual funds, and other related consulting fees.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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-Paragraph 9
-Subparagraph (a),(c)-(e)
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Total aggregate amount of all noninterest expense.

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Amount of expense related to estimated loss from loan and lease transactions.

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-Name Accounting Standards Codification
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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