INVESTMENTS - Information Regarding Pretax Realized Gains and Losses From Investments (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment losses realized	$ (977)	[1]	$ (1,901)	[1]	$ (459)	[2]
Derivative gains (losses)	151		(257)		(1)
Other	3		17		(1)
Total realized investment gains (losses)	(349)		(1,552)		(422)
Fixed maturities
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	(349)		(739)		(389)
Fixed maturities | Available-for-sale Securities
Gain (Loss) on Investments [Line Items]
Gross gains from sales	427		992		117
Gross losses from sales	(48)		(465)		(212)
Net gains (losses) from redemptions	2		69		1
Other-than-temporary impairment losses realized	(734)		(1,335)		(297)
Fixed maturities | Held-to-maturity Securities
Gain (Loss) on Investments [Line Items]
Net gains (losses) from redemptions	4		0		2
Perpetual securities
Gain (Loss) on Investments [Line Items]
Gross gains from sales	127		102		133
Gross losses from sales	(98)		(109)		0
Net gains (losses) from redemptions	60		0		0
Other-than-temporary impairment losses realized	(243)		(565)		(160)
Total realized investment gains (losses)	(154)		(572)		(27)
Equity securities
Gain (Loss) on Investments [Line Items]
Gross losses from sales	0		0		(2)
Other-than-temporary impairment losses realized	0		(1)		(2)
Total realized investment gains (losses)	0		(1)		(4)
Derivatives and other
Gain (Loss) on Investments [Line Items]
Total realized investment gains (losses)	$ 154		$ (240)		$ (2)

[1] Includes $597 and $1,286 for the years ended December 31, 2012 and 2011, respectively, for credit-related impairments; $353 and $615 for the years ended December 31, 2012 and 2011, respectively, from change in intent to sell securities; and $27 for the year ended December 31, 2012 for impairments due to severity and duration of decline in fair value

[2] Consisted completely of credit-related impairments