INTEREST INCOME AND EXPENSE (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Interest income
Loan interest, including fees	$ 15,542	$ 13,283
Deposits with banks	2,647	3,031
Securities borrowed and purchased under agreements to resell	7,822	5,174
Investments, including dividends	4,849	4,144
Trading account assets	4,128	2,747
Other interest-earning assets	1,235	1,016
Total interest income	36,223	29,395
Interest expense
Deposits	10,411	7,708
Securities loaned and sold under agreements to repurchase	6,966	3,566
Trading account liabilities	831	787
Short-term borrowings and other interest-bearing liabilities	1,956	1,649
Long-term debt	2,552	2,337
Total interest expense	22,716	16,047
Net interest income	13,507	13,348
Provision for credit losses on loans	2,422	1,737
Net interest income after provision for credit losses on loans	11,085	11,611
Consumer loans
Interest income
Loan interest, including fees	9,798	8,624
Corporate loans
Interest income
Loan interest, including fees	$ 5,744	$ 4,659

Interest and dividend income on all securities excluding trading securities.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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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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Amount of interest income, amortization of premium and accretion of discount, on investment in debt security measured at fair value with change in fair value recognized in net income (trading); classified as operating.

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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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