Line of Business Information - Summary of Line of Business (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Servicing fees	$ 1,351	$ 1,303	$ 3,986	$ 3,784
Management fees	419	368	1,198	931
Trading services	259	267	823	806
Securities finance	147	136	459	426
Processing fees and other	66	5	209	155
Total fee revenue	2,242	2,079	6,675	6,102
Net interest income	603	537	1,688	1,570
Gains (losses) related to investment securities, net	1	4	(39)	5
Total revenue	2,846	2,620	8,324	7,677
Provision for loan losses	3	0	4	8
Total expenses	2,021	1,984	6,138	5,894
Income before income tax expense	$ 822	$ 636	$ 2,182	$ 1,775
Pre-tax margin	29.00%	24.00%	26.00%	23.00%
Operating Segments \| Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,351	$ 1,303	$ 3,986	$ 3,784
Management fees	0	0	0	0
Trading services	239	248	768	760
Securities finance	147	136	459	426
Processing fees and other	65	12	203	164
Total fee revenue	1,802	1,699	5,416	5,134
Net interest income	606	536	1,691	1,567
Gains (losses) related to investment securities, net	1	4	(39)	5
Total revenue	2,409	2,239	7,068	6,706
Provision for loan losses	3	0	4	8
Total expenses	1,673	1,634	5,050	4,920
Income before income tax expense	$ 733	$ 605	$ 2,014	$ 1,778
Pre-tax margin	30.00%	27.00%	28.00%	27.00%
Operating Segments \| Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0	$ 0
Management fees	419	368	1,198	931
Trading services	20	19	55	46
Securities finance	0	0	0	0
Processing fees and other	1	(7)	6	(9)
Total fee revenue	440	380	1,259	968
Net interest income	(3)	1	(3)	3
Gains (losses) related to investment securities, net	0	0	0	0
Total revenue	437	381	1,256	971
Provision for loan losses	0	0	0	0
Total expenses	314	317	954	817
Income before income tax expense	$ 123	$ 64	$ 302	$ 154
Pre-tax margin	28.00%	17.00%	24.00%	16.00%
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	34	33	134	157
Income before income tax expense	$ (34)	$ (33)	$ (134)	$ (157)

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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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-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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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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