INTEREST REVENUE AND EXPENSE (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest revenue
Loan interest, including fees	$ 11,639	$ 10,745	$ 33,721	$ 31,082
Deposits with banks	629	486	1,554	1,156
Federal funds sold and securities borrowed or purchased under agreements to resell	1,425	858	3,800	2,348
Investments, including dividends	2,388	2,104	6,996	6,122
Trading account assets	1,655	1,429	4,789	4,175
Other interest	434	292	1,192	846
Total interest revenue	18,170	15,914	52,052	45,729
Interest expense
Deposits	2,580	1,775	6,821	4,793
Federal funds purchased and securities loaned or sold under agreements to repurchase	1,250	712	3,423	1,881
Trading account liabilities	273	169	724	462
Short-term borrowings	578	318	1,572	719
Long-term debt	1,687	1,405	4,873	4,126
Total interest expense	6,368	4,379	17,413	11,981
Net interest revenue	11,802	11,535	34,639	33,748
Provision for loan losses	1,906	2,146	5,504	5,487
Net interest revenue after provision for loan losses	9,896	9,389	29,135	28,261
Insurance fees and charges	$ 311	$ 301	$ 1,006	$ 935

The insurance fees and other charges paid for deposits.

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Interest and dividend income on all securities excluding trading securities.

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

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The aggregate interest expense incurred on short-term borrowings including commercial paper, Federal Home Loan Bank and Federal Reserve Bank advances and 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, after discount, accretion and premium amortization, of interest income and dividend income classified as other.

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Amount of expense related to loss from loan transactions.

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