Net interest revenue (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest revenue
Non-margin loans	$ 873	$ 727	$ 697
Margin loans	265	207	182
Securities:
Taxable	1,772	1,813	1,603
Exempt from federal income taxes	70	82	100
Total securities	1,842	1,895	1,703
Deposits with banks	104	104	238
Deposits with the Federal Reserve and other central banks	198	170	207
Federal funds sold and securities purchased under resale agreements	233	147	86
Trading assets	60	76	121
Total interest revenue	3,575	3,326	3,234
Interest expense
Deposits in domestic offices	41	30	29
Interest Expense, Foreign Deposits	(25)	7	54
Federal funds purchased and securities sold under repurchase agreements	36	(6)	(13)
Trading liabilities	6	9	25
Other borrowed funds	8	9	6
Commercial paper	5	2	2
Customer payables	12	7	9
Long-term debt	354	242	242
Total interest expense	437	300	354
Net interest revenue	3,138	3,026	2,880
Provision	(11)	160	(48)
Interest Income (Expense), after Provision for Loan Loss	$ 3,149	$ 2,866	$ 2,928

Interest income from loans used to purchase shares of stock.

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Interest Expense Customer Payables

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Interest income derived from funds deposited with the Federal Reserve and other central banks.

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Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

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Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on trading securities and other forms of securities that provide ownership interests.

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Interest expense incurred during the reporting period on commercial paper.

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Aggregate amount of interest expense on all deposits.

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The aggregate expense incurred on federal funds purchased and securities sold under agreements to repurchase. If amounts recognized as payables under repurchase agreements have been offset against amounts recognized as receivables under reverse repurchase agreements and reported as a net amount on the balance sheet, the income and expense from these agreements may be reported on a net basis.

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Interest expense on all foreign deposits.

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Aggregate amount of interest paid or due on all long-term debt.

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Interest expense incurred during the reporting period on other short-term borrowings.

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Interest expense incurred on short positions arising from sales of securities and other assets, which the entity does not own, to other parties. Trading liabilities includes the fair value of derivative contracts held for trading that are in loss positions.

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Interest income derived from funds deposited with both domestic and foreign financial institutions including funds in money market and other accounts.

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Amount of interest income or expense, including any amortization and accretion (as applicable) of discounts and premiums, including consideration of the provisions for loan, lease, credit, and other related losses.

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The net amount of operating interest income (expense).

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The aggregate interest income earned from (1) the lending of excess federal funds to another commercial bank requiring such for its legal reserve requirements and (2) securities purchased under agreements to resell.

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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