INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Variable Interest Entity [Line Items]
Securities held to maturity, fixed maturities, fair value	$ 54,841	$ 46,383
Liabilities	115,116	103,291
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Securities available for sale, fixed maturities, amortized cost	5,058	4,822
Securities available for sale, fixed maturities, fair value	5,787	5,350
Securities available for sale, perpetual securities, amortized cost	559	1,532
Securities available for sale, perpetual securities, fair value	574	1,290
Cost or Amortized Cost	289	643
Securities held to maturity, fixed maturities, fair value	287	566
Asset derivatives, amortized cost	191	375
Asset derivatives	191	375
Assets, amortized cost	6,097	7,372
Assets, fair value	6,839	7,581
Liability derivatives, amortized cost	399	531
Liability derivatives	399	531
Liabilities	399	531
Liabilities, fair value	$ 399	$ 531

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

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