Line of Business Information - Summary of Line of Business (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Servicing fees	$ 1,296	$ 1,242
Management fees	382	270
Trading services	275	272
Securities finance	133	134
Processing fees and other	112	52
Total fee revenue	2,198	1,970
Net interest income	510	512
Gains (losses) related to investment securities, net	(40)	2
Total revenue	2,668	2,484
Provision for loan losses	(2)	4
Total expenses	2,086	2,050
Income before income tax expense	$ 584	$ 430
Pre-tax margin	22.00%	17.00%
Operating Segments \| Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,296	$ 1,242
Management fees	0	0
Trading services	257	258
Securities finance	133	134
Processing fees and other	106	49
Total fee revenue	1,792	1,683
Net interest income	509	511
Gains (losses) related to investment securities, net	(40)	2
Total revenue	2,261	2,196
Provision for loan losses	(2)	4
Total expenses	1,728	1,687
Income before income tax expense	$ 535	$ 505
Pre-tax margin	24.00%	23.00%
Operating Segments \| Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0
Management fees	382	270
Trading services	18	14
Securities finance	0	0
Processing fees and other	6	3
Total fee revenue	406	287
Net interest income	1	1
Gains (losses) related to investment securities, net	0	0
Total revenue	407	288
Provision for loan losses	0	0
Total expenses	329	256
Income before income tax expense	$ 78	$ 32
Pre-tax margin	19.00%	11.00%
Other
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0
Management fees	0	0
Trading services	0	0
Securities finance	0	0
Processing fees and other	0	0
Total fee revenue	0	0
Net interest income	0	0
Gains (losses) related to investment securities, net	0	0
Total revenue	0	0
Provision for loan losses	0	0
Total expenses	29	107
Income before income tax expense	$ (29)	$ (107)

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(c)-(e)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
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-Topic 320
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-Section 50
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-Name Accounting Standards Codification
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-Paragraph 11B
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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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