INTEREST REVENUE AND EXPENSE (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Interest revenue
Loan interest, including fees	$ 11,993	$ 11,639	$ 35,942	$ 33,721
Deposits with banks	736	629	2,079	1,554
Securities borrowed or purchased under agreements to resell	1,745	1,425	5,422	3,800
Investments, including dividends	2,411	2,388	7,464	6,996
Trading account assets	1,893	1,655	5,719	4,789
Other interest	399	434	1,339	1,192
Total interest revenue	19,177	18,170	57,965	52,052
Interest expense
Deposits	3,369	2,580	9,680	6,821
Securities loaned or sold under agreements to repurchase	1,630	1,250	4,943	3,423
Trading account liabilities	345	273	992	724
Short-term borrowings	609	578	1,976	1,572
Long-term debt	1,583	1,687	5,024	4,873
Total interest expense	7,536	6,368	22,615	17,413
Net interest revenue	11,641	11,802	35,350	34,639
Provision for loan losses	2,062	1,906	6,095	5,504
Net interest revenue after provision for loan losses	9,579	9,896	29,255	29,135
Insurance fees and charges	$ 199	$ 311	$ 581	$ 1,006

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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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 credit loss expense (reversal of expense) for financing receivable.

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