INTEREST REVENUE AND EXPENSE (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Interest revenue
Loan interest, including fees	$ 11,628	$ 12,482
Deposits with banks	258	367
Federal funds sold and securities borrowed or purchased under agreements to resell	688	943
Investments, including dividends	1,802	1,910
Trading account assets	1,630	1,697
Other interest	159	138
Total interest revenue	16,165	17,537
Interest expense
Deposits	1,627	2,022
Federal funds purchased and securities loaned or sold under agreements to repurchase	609	695
Trading account liabilities	42	53
Short-term borrowings	163	208
Long-term debt	1,840	2,612
Total interest expense	4,281	5,590
Net interest revenue	11,884	11,947
Provision for loan losses	2,295	2,828
Net interest revenue after provision for loan losses	9,589	9,119
Insurance fees and charges	$ 299	$ 372

The insurance fees and other charges paid for deposits.

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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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Interest and dividend income on securities that are bought and held principally for the purpose of selling them in the near term ("trading securities") and on securities measured at fair value through earnings.

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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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The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

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Aggregate amount of interest expense on all deposits.

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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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Provision charged for the period based on estimated losses to be realized from loan transactions.

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