INVESTMENTS (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Investments summary
Securities available-for-sale, at fair value	$ 258,835	$ 274,572
Debt securities held-to-maturity	12,866	29,107
Non-marketable equity securities carried at fair value	7,754	6,602
Non-marketable equity securities carried at cost	7,202	7,883
Total investments	286,657	318,164
Securities available-for-sale
Securities available-for-sale, at fair value	258,835	274,572
Mortgage-backed securities
Investments summary
Securities available-for-sale, at fair value	45,261	26,506
Securities available-for-sale
Amortized cost	43,853	26,490
Gross unrealized gains	1,478	468
Gross unrealized losses	70	452
Securities available-for-sale, at fair value	45,261	26,506
U.S. government-sponsored agency guaranteed
Investments summary
Securities available-for-sale, at fair value	41,763	23,623
Securities available-for-sale
Amortized cost	40,353	23,433
Gross unrealized gains	1,456	425
Gross unrealized losses	46	235
Securities available-for-sale, at fair value	41,763	23,623
Prime
Investments summary
Securities available-for-sale, at fair value	130	1,826
Securities available-for-sale
Amortized cost	135	1,985
Gross unrealized gains		18
Gross unrealized losses	5	177
Securities available-for-sale, at fair value	130	1,826
Alt-A
Investments summary
Securities available-for-sale, at fair value	1	48
Securities available-for-sale
Amortized cost	1	46
Gross unrealized gains		2
Securities available-for-sale, at fair value	1	48
Subprime
Investments summary
Securities available-for-sale, at fair value		119
Securities available-for-sale
Amortized cost		119
Gross unrealized gains		1
Gross unrealized losses		1
Securities available-for-sale, at fair value		119
Non-U.S. residential
Investments summary
Securities available-for-sale, at fair value	2,884	316
Securities available-for-sale
Amortized cost	2,886	315
Gross unrealized gains	8	1
Gross unrealized losses	10
Securities available-for-sale, at fair value	2,884	316
Commercial.
Investments summary
Securities available-for-sale, at fair value	483	574
Securities available-for-sale
Amortized cost	478	592
Gross unrealized gains	14	21
Gross unrealized losses	9	39
Securities available-for-sale, at fair value	483	574
U.S. Treasury and federal agency securities
Investments summary
Securities available-for-sale, at fair value	81,514	102,062
Securities available-for-sale
Amortized cost	79,523	101,363
Gross unrealized gains	2,018	810
Gross unrealized losses	27	111
Securities available-for-sale, at fair value	81,514	102,062
U.S. Treasury
Investments summary
Securities available-for-sale, at fair value	40,041	58,448
Securities available-for-sale
Amortized cost	38,688	58,069
Gross unrealized gains	1,365	435
Gross unrealized losses	12	56
Securities available-for-sale, at fair value	40,041	58,448
Agency obligations
Investments summary
Securities available-for-sale, at fair value	41,473	43,614
Securities available-for-sale
Amortized cost	40,835	43,294
Gross unrealized gains	653	375
Gross unrealized losses	15	55
Securities available-for-sale, at fair value	41,473	43,614
State and municipal securities
Investments summary
Securities available-for-sale, at fair value	14,380	13,235
Securities available-for-sale
Amortized cost	16,818	15,660
Gross unrealized gains	136	75
Gross unrealized losses	2,574	2,500
Securities available-for-sale, at fair value	14,380	13,235
Foreign government
Investments summary
Securities available-for-sale, at fair value	82,988	99,679
Securities available-for-sale
Amortized cost	82,757	99,110
Gross unrealized gains	625	984
Gross unrealized losses	394	415
Securities available-for-sale, at fair value	82,988	99,679
Corporate
Investments summary
Securities available-for-sale, at fair value	16,574	16,170
Securities available-for-sale
Amortized cost	16,296	15,910
Gross unrealized gains	330	319
Gross unrealized losses	52	59
Securities available-for-sale, at fair value	16,574	16,170
Asset-backed securities
Investments summary
Securities available-for-sale, at fair value	9,912	9,048
Securities available-for-sale
Amortized cost	9,922	9,085
Gross unrealized gains	50	31
Gross unrealized losses	60	68
Securities available-for-sale, at fair value	9,912	9,048
Other debt securities
Investments summary
Securities available-for-sale, at fair value	2,162	1,912
Securities available-for-sale
Amortized cost	2,123	1,948
Gross unrealized gains	45	24
Gross unrealized losses	6	60
Securities available-for-sale, at fair value	2,162	1,912
Total debt securities AFS
Investments summary
Securities available-for-sale, at fair value	252,791	268,612
Securities available-for-sale
Amortized cost	251,292	269,566
Gross unrealized gains	4,682	2,711
Gross unrealized losses	3,183	3,665
Securities available-for-sale, at fair value	252,791	268,612
Marketable equity securities AFS
Investments summary
Securities available-for-sale, at fair value	6,044	5,960
Securities available-for-sale
Amortized cost	4,560	3,791
Gross unrealized gains	1,712	2,380
Gross unrealized losses	228	211
Securities available-for-sale, at fair value	6,044	5,960
Total securities AFS
Investments summary
Securities available-for-sale, at fair value	258,835	274,572
Securities available-for-sale
Amortized cost	255,852	273,357
Gross unrealized gains	6,394	5,091
Gross unrealized losses	3,411	3,876
Securities available-for-sale, at fair value	$ 258,835	$ 274,572

This item represents the gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized gains are the excess of the fair value of the Available-for-sale Securities over their carrying value as of the reporting date.

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This item represents the gross unrealized losses for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized losses are the excess of the carrying value of the Available-for-sale Securities over their fair value as of the reporting date.

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This element represents the fair value of non-marketable equity securities.

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- Definition

For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading. Such securities are reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 14

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 7

-Footnote 2

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

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- Definition

This element represents the aggregate carrying amount of all cost-method investments held by the Company. Generally, such investments do not have readily determinable fair values and are not required to be accounted for by the equity method. The carrying amount of such securities equates to cost, adjusted for other-than-temporary impairment. The cost method and lower-of-cost or market, an adaptation of the cost method, is generally followed for most investments in noncontrolled corporations, in some corporate joint ventures, and to a lesser extent in unconsolidated subsidiaries, particularly foreign.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 03-1

-Paragraph 22

-Subparagraph a

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 18

-Subparagraph a

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 4

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 4

-Subparagraph c

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 6

-Subparagraph a

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- Definition

For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity; such investments are measured at amortized cost (carrying value). The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 3

-Section A

-Paragraph 4, 5

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 17

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 7, 8, 9, 10, 11

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- Definition

Sum of the carrying amounts as of the balance sheet date of current and noncurrent investments.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph h

-Article 7

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