INVESTMENTS (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Total, Amortized Cost or Cost	$ 249,121,000,000	$ 247,789,000,000
Total, Gross Unrealized Gains	25,556,000,000	26,815,000,000
Total, Gross Unrealized Losses	(1,318,000,000)	(1,433,000,000)
Total, fair value	273,359,000,000	273,171,000,000
Total, Other-Than-Temporary Impairments in AOCI	1,886,000,000	1,450,000,000
Bonds available for sale
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	247,592,000,000	246,149,000,000
Available-for-sale Securities, Gross Unrealized Gains	23,958,000,000	25,206,000,000
Available-for-sale Securities, Gross Unrealized Losses	(1,299,000,000)	(1,396,000,000)
Available for Sale Securities, fair value	270,251,000,000	269,959,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	1,886,000,000	1,450,000,000
Other details of available-for-sale securities
Available for sale securities not rated or rated below investment grade	30,700,000,000	29,600,000,000
Bonds available for sale \| U.S. government and government sponsored entities
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	3,194,000,000	3,161,000,000
Available-for-sale Securities, Gross Unrealized Gains	303,000,000	323,000,000
Available-for-sale Securities, Gross Unrealized Losses	(1,000,000)	(1,000,000)
Available for Sale Securities, fair value	3,496,000,000	3,483,000,000
Bonds available for sale \| Obligations of states, municipalities and political subdivisions
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	32,683,000,000	33,042,000,000
Available-for-sale Securities, Gross Unrealized Gains	2,473,000,000	2,685,000,000
Available-for-sale Securities, Gross Unrealized Losses	(45,000,000)	(22,000,000)
Available for Sale Securities, fair value	35,111,000,000	35,705,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	2,000,000	2,000,000
Bonds available for sale \| Non-U.S. government
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	24,251,000,000	25,449,000,000
Available-for-sale Securities, Gross Unrealized Gains	1,222,000,000	1,395,000,000
Available-for-sale Securities, Gross Unrealized Losses	(98,000,000)	(44,000,000)
Available for Sale Securities, fair value	25,375,000,000	26,800,000,000
Bonds available for sale \| Corporate debt
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	136,299,000,000	135,728,000,000
Available-for-sale Securities, Gross Unrealized Gains	14,579,000,000	15,848,000,000
Available-for-sale Securities, Gross Unrealized Losses	(572,000,000)	(464,000,000)
Available for Sale Securities, fair value	150,306,000,000	151,112,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	107,000,000	115,000,000
Bonds available for sale \| Mortgage backed, asset backed and collateralized
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	51,165,000,000	48,769,000,000
Available-for-sale Securities, Gross Unrealized Gains	5,381,000,000	4,955,000,000
Available-for-sale Securities, Gross Unrealized Losses	(583,000,000)	(865,000,000)
Available for Sale Securities, fair value	55,963,000,000	52,859,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	1,777,000,000	1,333,000,000
Bonds available for sale \| Residential mortgage backed securities (RMBS)
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	32,568,000,000	31,330,000,000
Available-for-sale Securities, Gross Unrealized Gains	3,777,000,000	3,379,000,000
Available-for-sale Securities, Gross Unrealized Losses	(219,000,000)	(317,000,000)
Available for Sale Securities, fair value	36,126,000,000	34,392,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	1,708,000,000	1,330,000,000
Bonds available for sale \| Commercial mortgage-backed securities (CMBS)
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	9,841,000,000	9,699,000,000
Available-for-sale Securities, Gross Unrealized Gains	785,000,000	811,000,000
Available-for-sale Securities, Gross Unrealized Losses	(215,000,000)	(376,000,000)
Available for Sale Securities, fair value	10,411,000,000	10,134,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	6,000,000	(54,000,000)
Bonds available for sale \| Collateralized Debt Obligations/Asset Backed Securities (CDO/ABS)
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	8,756,000,000	7,740,000,000
Available-for-sale Securities, Gross Unrealized Gains	819,000,000	765,000,000
Available-for-sale Securities, Gross Unrealized Losses	(149,000,000)	(172,000,000)
Available for Sale Securities, fair value	9,426,000,000	8,333,000,000
Available-for-sale Securities, Other-Than- Temporary Impairments in AOCI	63,000,000	57,000,000
Equity securities available for sale
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	1,529,000,000	1,640,000,000
Available-for-sale Securities, Gross Unrealized Gains	1,598,000,000	1,609,000,000
Available-for-sale Securities, Gross Unrealized Losses	(19,000,000)	(37,000,000)
Available for Sale Securities, fair value	3,108,000,000	3,212,000,000
Equity securities available for sale \| Common Stock
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	1,382,000,000	1,492,000,000
Available-for-sale Securities, Gross Unrealized Gains	1,559,000,000	1,574,000,000
Available-for-sale Securities, Gross Unrealized Losses	(19,000,000)	(37,000,000)
Available for Sale Securities, fair value	2,922,000,000	3,029,000,000
Equity securities available for sale \| Preferred Stock
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	55,000,000	55,000,000
Available-for-sale Securities, Gross Unrealized Gains	27,000,000	23,000,000
Available for Sale Securities, fair value	82,000,000	78,000,000
Equity securities available for sale \| Mutual Funds
Reconciliation of amortized cost and fair value of available for sale securities and other invested assets carried at fair value
Available-for-sale Securities, Amortized Cost or Cost	92,000,000	93,000,000
Available-for-sale Securities, Gross Unrealized Gains	12,000,000	12,000,000
Available for Sale Securities, fair value	$ 104,000,000	$ 105,000,000

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Represents the total cost of available-for-sale securities and private equity and hedge fund investments carried at fair value for which unrealized gains and losses are recognized in other comprehensive income, excluding available for sale securities, carried at fair value, of businesses held for sale.

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Represents the total fair market value of available-for-sale securities and private equity and hedge fund investments carried at fair value for which unrealized gains and losses are recognized in other comprehensive income, excluding available for sale securities, carried at fair value, of businesses held for sale.

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No definition available.

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The amount of Available-for-sale Securities that are below investment grade or not rated.

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No definition available.

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Subsequent to impairment measurement date and before tax amount of other than temporary impairment (OTTI) on a debt security, categorized as either available-for-sale or held-to-maturity, recognized in other comprehensive income (loss).

+ References

No definition available.

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The amount of other-than-temporary impairment losses in Accumulated other comprehensive loss (AOCI), which are not recognized in earnings. Amount includes unrealized gains and losses on impaired securities relating to changes in the value of such securities subsequent to the impairment measurement date.

+ References

No definition available.

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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 Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

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This item represents the gross unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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No definition available.

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