INVESTMENTS - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 investment	Dec. 31, 2012 investment	Dec. 31, 2011 investment
Schedule of Investments [Line Items]
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, number of investments	2	7	13
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, amortized cost	$ 492	$ 1,200	$ 2,500
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, aggregate unrealized gain (loss)	153	290	334
Perpetual securities, interest coupons that were fixed at issuance subsequently change to a floating short-term interest rate	floating short-term interest rate of 125 to more than 300 basis points above an appropriate market index
Unrealized Gain (Loss)	1,523	3,932
Percentage that the lending policy requires that the fair value of the securities and/or unrestricted cash received as collateral be of the fair value of the loaned securities	102.00%
Fair value of debt securities on deposit with regulatory authorities in the United States and Japan	15
Variable Interest Entity, Not Consolidated
Schedule of Investments [Line Items]
Securities available for sale, fixed maturities, fair value	6,916	8,350
Number of issuers of VIEs not-consolidated	173
Perpetual securities
Schedule of Investments [Line Items]
Economic maturity date (in years)	25 years
Unrealized Gain (Loss)	(40)	89
Perpetual securities | Lower Limit
Schedule of Investments [Line Items]
Perpetual securities, floating short-term interest rate basis point above market index	1.25%
Perpetual securities | Minimum Upper Limit
Schedule of Investments [Line Items]
Perpetual securities, floating short-term interest rate basis point above market index	3.00%
Parent Company
Schedule of Investments [Line Items]
Available-for-sale fixed-maturity securities, amortized cost	322
Securities available for sale, fixed maturities, fair value	$ 332	$ 156