INTEREST REVENUE AND EXPENSE (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Interest revenue
Loan interest, including fees	$ 12,671	$ 13,332	$ 37,728	$ 42,232
Deposits with banks	423	318	1,342	899
Federal funds sold and securities purchased under agreements to resell	948	807	2,689	2,340
Investments, including dividends	1,925	2,551	6,461	8,515
Trading account assets	2,073	2,026	6,293	5,909
Other interest	106	277	373	555
Total interest revenue	18,145	19,311	54,886	60,450
Interest expense
Deposits	2,228	2,130	6,472	6,246
Federal funds purchased and securities loaned or sold under agreements to repurchase	796	671	2,466	2,122
Trading account liabilities	91	108	343	277
Short-term borrowings	155	213	493	704
Long-term debt	2,761	3,061	8,748	9,605
Total interest expense	6,031	6,183	18,522	18,954
Net interest revenue	12,114	13,128	36,364	41,496
Provision for loan losses	3,049	5,666	9,129	20,555
Net interest revenue after provision for loan losses	9,065	7,462	27,235	20,941
Insurance fees and charges	$ 387	$ 226	$ 974	$ 691

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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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.

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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 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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Net interest and dividend 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, if any.

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Amount of net interest income or expense derived from banking operations.

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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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Includes all other interest income, net of discount accretion and premium amortization, and dividend income. It may include dividend income from equity securities that do not have readily determinable fair values that are reportable in Other Assets, and interest income on interest-only strips receivable (not in the form of a security) that are included in Other Assets.

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Allowance expensed for the period based on estimated losses to be realized from loan transactions.

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