INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Variable Interest Entity [Line Items]
Securities held to maturity, fixed maturities, amortized cost	$ 34,242us-gaap_HeldToMaturitySecurities	$ 44,415us-gaap_HeldToMaturitySecurities
Securities held to maturity, fixed maturities, fair value	38,497	45,846
Asset derivatives	802us-gaap_DerivativeAssets	488us-gaap_DerivativeAssets
Assets, fair value	73,901us-gaap_AssetsFairValueDisclosure	64,532us-gaap_AssetsFairValueDisclosure
Liability derivatives	2,423us-gaap_DerivativeLiabilities	837us-gaap_DerivativeLiabilities
Liabilities	101,420us-gaap_Liabilities	106,687us-gaap_Liabilities
Liabilities, fair value disclosure	2,423us-gaap_LiabilitiesFairValueDisclosure	837us-gaap_LiabilitiesFairValueDisclosure
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	3,020	4,109
Securities available for sale, fixed maturities, fair value	4,166	4,843
Securities available for sale, perpetual securities, amortized cost	405	463
Securities available for sale, perpetual securities, fair value	429	468
Securities held to maturity, fixed maturities, amortized cost	83	237
Securities held to maturity, fixed maturities, fair value	84	236
Asset derivatives, amortized cost	106	106
Asset derivatives	106	106
Assets, amortized cost	3,614	4,915
Assets, fair value	4,785	5,653
Liability derivatives, amortized cost	318	207
Liability derivatives	318	207
Liabilities	318	207
Liabilities, fair value disclosure	$ 318	$ 207

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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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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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 liabilities 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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