Line of Business Information - Summary of Line of Business (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Servicing fees	$ 5,073	$ 5,153	$ 5,108
Management fees	1,292	1,174	1,207
Trading services	1,099	1,146	1,084
Securities finance	562	496	437
Processing fees and other	90	309	174
Total fee revenue	8,116	8,278	8,010
Net interest revenue	2,084	2,088	2,260
Gains (losses) related to investment securities, net	7	(6)	4
Total revenue	10,207	10,360	10,274
Provision for loan losses	10	12	10
Total expenses	8,077	8,050	7,827
Income before income tax expense	$ 2,120	$ 2,298	$ 2,437
Pre-tax margin	21.00%	22.00%	24.00%
Average assets	$ 229,700	$ 250,500	$ 238,100
Investment Servicing
Segment Reporting Information [Line Items]
Average assets	225,300	246,600	234,200
Investment Management
Segment Reporting Information [Line Items]
Average assets	4,400	3,900	3,900
Operating Segments \| Investment Servicing
Segment Reporting Information [Line Items]
Servicing fees	5,073	5,153	5,108
Management fees	0	0	0
Trading services	1,052	1,108	1,039
Securities finance	562	496	437
Processing fees and other	105	325	179
Total fee revenue	6,792	7,082	6,763
Net interest revenue	2,081	2,086	2,245
Gains (losses) related to investment securities, net	7	(6)	4
Total revenue	8,880	9,162	9,012
Provision for loan losses	10	12	10
Total expenses	6,660	6,990	6,648
Income before income tax expense	$ 2,210	$ 2,160	$ 2,354
Pre-tax margin	25.00%	24.00%	26.00%
Operating Segments \| Investment Management
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0
Management fees	1,292	1,174	1,207
Trading services	47	38	45
Securities finance	0	0	0
Processing fees and other	(15)	(16)	(5)
Total fee revenue	1,324	1,196	1,247
Net interest revenue	3	2	15
Gains (losses) related to investment securities, net	0	0	0
Total revenue	1,327	1,198	1,262
Provision for loan losses	0	0	0
Total expenses	1,218	962	960
Income before income tax expense	$ 109	$ 236	$ 302
Pre-tax margin	8.00%	20.00%	24.00%
Other
Segment Reporting Information [Line Items]
Servicing fees	$ 0	$ 0	$ 0
Management fees	0	0	0
Trading services	0	0	0
Securities finance	0	0	0
Processing fees and other	0	0	0
Total fee revenue	0	0	0
Net interest revenue	0	0	0
Gains (losses) related to investment securities, net	0	0	0
Total revenue	0	0	0
Provision for loan losses	0	0	0
Total expenses	199	98	219
Income before income tax expense	$ (199)	$ (98)	$ (219)

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Total Average Assets

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

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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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