FAIR VALUE MEASUREMENTS - Additional Information (Detail) (USD $)	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 Fair Value, Measurements, Recurring Level 2	Dec. 31, 2009 Fair Value, Measurements, Recurring Level 2	Sep. 30, 2011 Fair Value Based on Discounted Cash Flow Pricing Model	Sep. 30, 2011 Interest Rates	Sep. 30, 2011 Credit Spreads	Sep. 30, 2011 Interest Rate Volatility
Fair Value, Measurement Inputs, Disclosure [Line Items]
Percentage of investments valued by obtaining quoted market prices from investment custodian			51.00%
Percentage of fair value of investments using DCF pricing model			46.00%
Amount of Level 2 investments that were reclassified upon the adoption of new accounting guidance				$ 1,000,000,000
Magnitude of movement						0.50%	0.50%	50.00%
Fair values of available-for-sale fixed maturity and perpetual securities valued by our DCF pricing model					19,100,000,000
Securities held to maturity, Fixed maturities, fair value	$ 40,111,000,000	$ 30,469,000,000			$ 26,700,000,000