INVESTMENTS - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended						9 Months Ended	12 Months Ended
	Sep. 30, 2013 investment	Jun. 30, 2013 investment	Mar. 31, 2013 investment	Sep. 30, 2012 investment	Jun. 30, 2012 investment	Mar. 31, 2012 investment	Sep. 30, 2013	Dec. 31, 2012
Schedule of Investments [Line Items]
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, number of investments	0	1	0	1	5	1
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, amortized cost		$ 297		$ 206	$ 842	$ 122
Reclassified investments from the held-to-maturity portfolio to the available-for-sale portfolio, aggregate unrealized gain (loss)		(108)			(268)	(23)
Unrealized Gain (Loss)							164	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%						102.00%
Variable Interest Entity, Not Consolidated
Schedule of Investments [Line Items]
Securities available for sale, fixed maturities, fair value	6,954						6,954	8,350
Number of issuers of VIEs not-consolidated							172
Perpetual Securities
Schedule of Investments [Line Items]
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
Maturity date (in years)							25 years
Unrealized Gain (Loss)							(352)	89
Perpetual Securities | Tier I
Schedule of Investments [Line Items]
Unrealized Gain (Loss)							(126)	(48)
Perpetual Securities | Upper Tier II
Schedule of Investments [Line Items]
Unrealized Gain (Loss)							(161)	94
Perpetual Securities | Lower Limit
Schedule of Investments [Line Items]
Perpetual securities, floating short-term interest rate basis point above market index	1.25%						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%						3.00%
Parent Company
Schedule of Investments [Line Items]
Available-for-sale fixed-maturity securities, amortized cost	295						295
Securities available for sale, fixed maturities, fair value	$ 307						$ 307