INVESTMENTS - Investments in Variable Interest Entities (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Variable Interest Entity [Line Items]
Cost or Amortized Cost	$ 45,204	$ 54,426
Securities held to maturity, fixed maturities, fair value	47,047	54,841
Asset derivatives	430	345
Assets, fair value	62,459	63,964
Liabilities	105,003	115,116
Liabilities, Fair Value Disclosure	643	934
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	4,721	5,058
Securities available for sale, fixed maturities, fair value	5,377	5,787
Securities available for sale, perpetual securities, amortized cost	520	559
Securities available for sale, perpetual securities, fair value	455	574
Cost or Amortized Cost	266	289
Securities held to maturity, fixed maturities, fair value	259	287
Asset derivative, amortized cost	158	191
Asset derivatives	158	191
Assets, amortized cost	5,665	6,097
Assets, fair value	6,249	6,839
Liability derivatives, amortized cost	371	399
Liability derivatives	371	399
Liabilities	371	399
Liabilities, Fair Value Disclosure	$ 371	$ 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.

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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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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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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 values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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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.

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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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This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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