INTEREST REVENUE AND EXPENSE (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Interest revenue
Loan interest, including fees	$ 8,909	$ 11,250
Deposits with banks	145	527
Securities borrowed and purchased under agreements to resell	294	1,208
Investments, including dividends	1,752	2,281
Trading account assets	1,337	1,590
Other interest-bearing assets	97	283
Total interest revenue	12,534	17,139
Interest expense
Deposits	1,052	2,614
Securities loaned and sold under agreements to repurchase	253	1,085
Trading account liabilities	114	239
Short-term borrowings and other interest-bearing liabilities	31	384
Long-term debt	918	1,325
Total interest expense	2,368	5,647
Net interest revenue	10,166	11,492
Provision for credit losses on loans	(1,479)	6,377
Net interest revenue after provision for credit losses on loans	11,645	5,115
Insurance fees and charges	$ 340	$ 225

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

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