INVESTMENTS (Details 4) (USD $) In Millions	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Debt Securities Held-to-Maturity
Carrying value	$ 14,910	$ 29,107
Mortgage-backed securities \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	12,686	23,190
Net unrealized loss recognized in AOCI	2,682	4,691
Carrying value	10,004	18,499
Gross unrecognized gains	263	1,201
Gross unrecognized losses	384	417
Fair value	9,883	19,283
Prime \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	1,098	4,748
Net unrealized loss recognized in AOCI	210	794
Carrying value	888	3,954
Gross unrecognized gains	28	379
Gross unrecognized losses	3	11
Fair value	913	4,322
Alt-A \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	5,641	11,816
Net unrealized loss recognized in AOCI	1,697	3,008
Carrying value	3,944	8,808
Gross unrecognized gains	19	536
Gross unrecognized losses	175	166
Fair value	3,788	9,178
Subprime \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	445	708
Net unrealized loss recognized in AOCI	48	75
Carrying value	397	633
Gross unrecognized gains		9
Gross unrecognized losses	60	72
Fair value	337	570
Non-U.S. residential \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	4,758	5,010
Net unrealized loss recognized in AOCI	725	793
Carrying value	4,033	4,217
Gross unrecognized gains	215	259
Gross unrecognized losses	93	72
Fair value	4,155	4,404
Commercial. \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	744	908
Net unrealized loss recognized in AOCI	2	21
Carrying value	742	887
Gross unrecognized gains	1	18
Gross unrecognized losses	53	96
Fair value	690	809
State and municipal securities \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	1,547	2,523
Net unrealized loss recognized in AOCI	96	127
Carrying value	1,451	2,396
Gross unrecognized gains	128	11
Gross unrecognized losses	199	104
Fair value	1,380	2,303
Corporate \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	2,269	6,569
Net unrealized loss recognized in AOCI	8	145
Carrying value	2,261	6,424
Gross unrecognized gains	7	447
Gross unrecognized losses	142	267
Fair value	2,126	6,604
Asset-based financing \| Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	1,245	1,855
Net unrealized loss recognized in AOCI	51	67
Carrying value	1,194	1,788
Gross unrecognized gains	24	57
Gross unrecognized losses	15	54
Fair value	1,203	1,791
Reclassification of debt securities from held-to-maturity to trading account assets
Debt Securities Held-to-Maturity
Amortized cost	17,747	34,137
Net unrealized loss recognized in AOCI	2,837	5,030
Carrying value	14,910	29,107
Gross unrecognized gains	422	1,716
Gross unrecognized losses	740	842
Fair value	14,592	29,981
Net unrealized losses recorded in AOCI and excluded from gross unrecognized losses	$ 2,800	$ 5,000

This item represents the cost of investments in debt securities which are categorized as held-to-maturity, net of adjustments for accretion and amortization. This item does not include any adjustments related to credit losses that are considered other-than-temporary impairments.

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- Definition

This item represents the adjustments to the amortized cost of investments held-to-maturity debt securities related to credit losses that are considered other-than-temporary impairments.

+ Details

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As of the balance sheet date, the excess of fair value over carrying value of a debt security categorized as held-to-maturity.

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- Definition

As of the balance sheet date, the excess of carrying value over fair value of a debt security categorized as held-to-maturity.

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- Definition

The amount of other than temporary impairment loss on a debt security, categorized as Held-to-maturity, related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. This amount, which includes the portion attributable to the noncontrolling interest, if any, is a portion of the deduction from the total impairment losses of investments (before taxes) presented on the income statement; this amount is also referred to as the amount incurred by the reporting entity or the consolidated entity.

+ Details

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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

This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 137

+ Details

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