FAIR VALUE ELECTIONS (Details) (USD $) In Millions	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Assets
Federal funds sold and securities borrowed or purchased under agreements to resell, selected portfolios of securities purchased under agreements to resell and securities borrowed	$ 163,439	$ 87,512
Investments	266,589	281,174
Loans	5,363	4,372
Liabilities
Federal funds purchased and securities loaned or sold under agreements to repurchase	135,724	121,193
Short-term borrowings	1,585	2,429
Long-term debt, at fair value	25,190	25,997
Fair value, fair value option
Assets
Federal funds sold and securities borrowed or purchased under agreements to resell, selected portfolios of securities purchased under agreements to resell and securities borrowed	163,439	87,512
Trading account assets	14,982	14,289
Investments	631	646
Loans	5,363	4,372
Other assets	9,319	12,013
Total assets elected under fair value option	193,734	118,832
Liabilities
Interest-bearing deposits	1,519	1,265
Federal funds purchased and securities loaned or sold under agreements to repurchase	135,724	121,193
Trading account liabilities	2,453	3,953
Short-term borrowings	1,585	2,429
Long-term debt, at fair value	25,190	25,997
Total liabilities elected under fair value option	166,471	154,837
Fair value, fair value option \| Corporate loans.
Assets
Loans	4,056	2,627
Fair value, fair value option \| Consumer loans.
Assets
Loans	1,307	1,745
Fair value, fair value option \| Mortgage servicing rights
Assets
Other assets	2,852	4,554
Fair value, fair value option \| Certain mortgage loans (HFS)
Assets
Other assets	6,414	7,230
Fair value, fair value option \| Certain equity method investments
Assets
Other assets	53	229
Changes in fair value gains (losses)
Assets
Federal funds sold and securities borrowed or purchased under agreements to resell, selected portfolios of securities purchased under agreements to resell and securities borrowed	(23)	669
Trading account assets	(1,030)	356
Investments	243	32
Loans	(202)	42
Other assets	(1,279)	(1,824)
Total assets Changes in fair value gain (loss) on assets	(2,291)	(725)
Liabilities
Interest-bearing deposits	55	10
Federal funds purchased and securities loaned or sold under agreements to repurchase Selected portfolios of securities sold under agreements to repurchase and securities loaned	(106)	53
Trading account liabilities	604	(223)
Short-term borrowings	174	36
Long-term debt	2,085	(21)
Fair value option changes in fair value gain (loss) on liabilities	2,812	(145)
Changes in fair value gains (losses) \| Corporate loans.
Assets
Loans	78	(166)
Changes in fair value gains (losses) \| Consumer loans.
Assets
Loans	(280)	208
Changes in fair value gains (losses) \| Mortgage servicing rights
Assets
Other assets	(1,426)	(1,976)
Changes in fair value gains (losses) \| Certain mortgage loans (HFS)
Assets
Other assets	158	188
Changes in fair value gains (losses) \| Certain equity method investments
Assets
Other assets	$ (11)	$ (36)

This element represents the fair value of total assets for which it has been opted to apply fair value measurement for financial reporting purposes.

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- Definition

The amount of gains and losses from fair value changes in assets, which are elected under fair value option, included in earnings during the period.

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- Definition

The amount of gains and losses from fair value changes in Federal funds purchased and securities loaned or sold under agreements to repurchase, at fair value, which are elected under fair value option, included in earnings during the period.

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- Definition

The amount of gains and losses from fair value changes in Federal funds sold and securities borrowed or purchased under agreements to resell, which are elected under fair value option, included in earnings during the period.

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- Definition

The amount of gains and losses from fair value changes in interest bearing deposit liabilities, which are elected under fair value option, included in earnings during the period.

+ Details

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The amount of gains and losses from fair value changes in investments, which are elected under fair value option, included in earnings during the period.

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The amount of gains and losses from fair value changes in liabilities, which are elected under fair value option, included in earnings during the period.

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- Definition

The amount of gains and losses from fair value changes in loans receivable, which are elected under fair value option, included in earnings during the period.

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The amount of gains and losses from fair value changes in long-term borrowings, at fair value, which are elected under fair value option, included in earnings during the period.

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The amount of gains and losses from fair value changes in other assets, which are elected under fair value option, included in earnings during the period.

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- Definition

The amount of gains and losses from fair value changes in short-term borrowings, at fair value, which are elected under fair value option, included in earnings during the period.

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The amount of gains and losses from fair value changes in trading account assets, which are elected under fair value option, included in earnings during the period.

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The amount of gains and losses from fair value changes in trading account liabilities, at fair value, which are elected under fair value option, included in earnings during the period.

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- Definition

The Fair Value disclosure of the amount shown on the books that a bank with insufficient reserves borrows, at the federal funds rate, from another bank to meet its reserve requirements and the amount of securities that an institution sells and agrees to repurchase at a specified date for a specified price, net of any reductions or offsets.

+ Details

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- Definition

This element represents the portion of interest-bearing deposits valued at fair value by the entity.

+ Details

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- Definition

This element represents the fair value of total liabilities for which it has been opted to apply fair value measurement for financial reporting purposes.

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- Definition

For an unclassified balance sheet, the Fair Value disclosure of the total of (current and noncurrent) carrying amounts of long-term borrowings as of the balance sheet date, which may include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of long-term debt.

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- Definition

This element represents the fair value of other assets for which it has been opted to apply fair value measurement for financial reporting purposes.

+ Details

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- Definition

Reflects the Fair Value disclosure of the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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This element represents the fair value of trading account assets for which it has been opted to apply fair value measurement for financial reporting purposes.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. The amount shown on an entity's books for federal funds sold and securities borrowed or purchased under agreements to resell.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 14

-Paragraph 4

-IssueDate 2006-05-01

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investment securities as of the balance sheet date which may include marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph a

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph a, f, g

-Article 7

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents loan receivable as presented on the statement of financial position which may include mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts, or any other loans which are due the Company as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 4

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents those liabilities that are incurred for the purpose of generating a profit from short-term fluctuations in price as part of a bank's or company's market-making, hedging and proprietary trading. Examples include short positions in securities, derivatives and commodities.

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