INTEREST REVENUE AND EXPENSE (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Interest revenue
Loan interest, including fees	$ 10,652	$ 10,229	$ 30,798	$ 29,739
Deposits with banks	486	247	1,156	703
Federal funds sold and securities borrowed or purchased under agreements to resell	858	636	2,347	1,947
Investments, including dividends	2,104	1,887	6,122	5,679
Trading account assets	1,429	1,433	4,176	4,399
Other interest	292	221	846	709
Total interest revenue	15,821	14,653	45,445	43,176
Interest expense
Deposits	1,775	1,443	4,793	3,953
Federal funds purchased and securities loaned or sold under agreements to repurchase	712	459	1,881	1,488
Trading account liabilities	169	102	462	286
Short-term borrowings	318	90	719	300
Long-term debt	1,405	1,080	4,126	3,207
Total interest expense	4,379	3,174	11,981	9,234
Net interest revenue	11,442	11,479	33,464	33,942
Provision for loan losses	2,146	1,746	5,487	5,022
Net interest revenue after provision for loan losses	9,296	9,733	27,977	28,920
Insurance fees and charges	$ 301	$ 336	$ 936	$ 838

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2-3)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e24721-111560

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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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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