INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Variable Interest Entity [Line Items]
Cost or Amortized Cost	$ 42,718	$ 54,426
Securities held to maturity, fixed maturities, fair value	42,761	54,841
Asset derivatives	620	345
Assets, fair value	61,674	63,964
Liability derivatives	447	934
Liabilities	102,617	115,116
Liabilities, Fair Value Disclosure	447	934
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	4,636	5,058
Securities available for sale, fixed maturities, fair value	5,022	5,787
Securities available for sale, perpetual securities, amortized cost	500	559
Securities available for sale, perpetual securities, fair value	450	574
Cost or Amortized Cost	254	289
Securities held to maturity, fixed maturities, fair value	240	287
Asset derivative, amortized cost	135	191
Asset derivatives	135	191
Assets, amortized cost	5,525	6,097
Assets, fair value	5,847	6,839
Liability derivatives, amortized cost	284	399
Liability derivatives	284	399
Liabilities	284	399
Liabilities, Fair Value Disclosure	$ 284	$ 399

Assets, Amortized Cost Disclosure

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For an unclassified balance sheet, total of perpetual securities categorized as neither held-to-maturity nor trading. Perpetual securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income, a separate component of shareholders' equity, 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 cost basis.

+ References

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This item represents the aggregate amortized cost of investments in perpetual securities as of the balance sheet date and which are categorized as available-for-sale.

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Derivative assets amortized cost disclosure

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Derivative liabilities amortized cost disclosure

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Fair value of financial and nonfinancial obligations.

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