Line of Business Information - Summary of Line of Business (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Servicing fees	$ 1,303	$ 1,289	$ 3,784	$ 3,876
Management fees	368	287	931	892
Trading services	267	294	806	899
Securities finance	136	113	426	369
Processing fees and other	5	120	155	198
Total fee revenue	2,079	2,103	6,102	6,234
Net interest revenue	537	513	1,570	1,594
Gains (losses) related to investment securities, net	4	(2)	5	(6)
Total revenue	2,620	2,614	7,677	7,822
Provision for loan losses	0	5	8	11
Total expenses	1,984	1,962	5,894	6,193
Income before income tax expense	$ 636	$ 647	$ 1,775	$ 1,618
Pre-tax margin	24.00%	25.00%	23.00%	21.00%
Operating Segments \| Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	$ 1,303	$ 1,289	$ 3,784	$ 3,876
Management fees	0	0	0	0
Trading services	254	283	771	869
Securities finance	136	113	426	369
Processing fees and other	6	131	153	212
Total fee revenue	1,699	1,816	5,134	5,326
Net interest revenue	536	514	1,567	1,593
Gains (losses) related to investment securities, net	4	(2)	5	(6)
Total revenue	2,239	2,328	6,706	6,913
Provision for loan losses	0	5	8	11
Total expenses	1,634	1,673	4,920	5,389
Income before income tax expense	$ 605	$ 650	$ 1,778	$ 1,513
Pre-tax margin	27.00%	28.00%	27.00%	22.00%
Operating Segments \| Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0	$ 0
Management fees	368	287	931	892
Trading services	13	11	35	30
Securities finance	0	0	0	0
Processing fees and other	(1)	(11)	2	(14)
Total fee revenue	380	287	968	908
Net interest revenue	1	(1)	3	1
Gains (losses) related to investment securities, net	0	0	0	0
Total revenue	381	286	971	909
Provision for loan losses	0	0	0	0
Total expenses	317	204	817	711
Income before income tax expense	$ 64	$ 82	$ 154	$ 198
Pre-tax margin	17.00%	29.00%	16.00%	22.00%
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 revenue	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	33	85	157	93
Income before income tax expense	$ (33)	$ (85)	$ (157)	$ (93)

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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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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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
-Topic 942
-SubTopic 225
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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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