Line of Business Information - Summary of Line of Business (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Servicing fees	$ 1,242	$ 1,268
Management fees	270	301
Trading services	272	324
Securities finance	134	101
Processing fees and other	52	61
Total fee revenue	1,970	2,055
Net interest revenue	512	546
Gains (losses) related to investment securities, net	2	(1)
Total revenue	2,484	2,600
Provision for loan losses	4	4
Total expenses	2,050	2,097
Income before income tax expense	$ 430	$ 499
Pre-tax margin	17.00%	19.00%
Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,242	$ 1,268
Management fees	0	0
Trading services	262	315
Securities finance	134	101
Processing fees and other	45	59
Total fee revenue	1,683	1,743
Net interest revenue	511	545
Gains (losses) related to investment securities, net	2	(1)
Total revenue	2,196	2,287
Provision for loan losses	4	4
Total expenses	1,687	1,836
Income before income tax expense	$ 505	$ 447
Pre-tax margin	23.00%	20.00%
Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0
Management fees	270	301
Trading services	10	9
Securities finance	0	0
Processing fees and other	7	2
Total fee revenue	287	312
Net interest revenue	1	1
Gains (losses) related to investment securities, net	0	0
Total revenue	288	313
Provision for loan losses	0	0
Total expenses	256	256
Income before income tax expense	$ 32	$ 57
Pre-tax margin	11.00%	18.00%
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 revenue	0	0
Gains (losses) related to investment securities, net	0	0
Total revenue	0	0
Provision for loan losses	0	0
Total expenses	107	5
Income before income tax expense	$ (107)	$ (5)

Pre-tax margin

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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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Fee and commission revenue earned from sources not otherwise specified in the existing taxonomy.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ 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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No definition available.

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Fees and commissions from underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, and other related consulting fees. Include fees and commissions from securities brokerage activities, from the sale and servicing of mutual funds, from the purchase and sale of securities and money market instruments where the bank is acting as agent for other banks or customers, and from the lending of securities owned by the bank or by bank customers (exclusive of trading revenue). Also includes the bank's proportionate share of the income or loss before extraordinary items and other adjustments from its investments in: unconsolidated subsidiaries, associated companies and corporate joint ventures, unincorporated joint ventures, general partnerships, and limited partnerships over which the bank exercises significant influence and that are principally engaged in investment banking, advisory, brokerage, or securities underwriting activities.

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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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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)
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-Name Accounting Standards Codification
-Topic 225
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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)
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-Name Accounting Standards Codification
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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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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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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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