DERIVATIVE FINANCIAL INSTRUMENTS (Details) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011		Sep. 30, 2012	Sep. 30, 2011		Dec. 31, 2011
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross	$ (116,663,000)	$ (97,445,000)	[1]	$ (194,340,000)	$ (145,354,000)	[1]
Notional Amount, Other long-term investments	6,706,181,000			6,706,181,000			5,948,784,000
Fair Value, Other long-term investments	134,021,000			134,021,000			54,645,000
Notional Amount, Other liabilities	8,862,660,000			8,862,660,000			7,321,905,000
Fair Value, Other liabilities	640,426,000			640,426,000			455,710,000
Derivatives not designated as hedging instruments
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(32,534,000)	23,435,000		(69,106,000)	(244,000)
Realized investment gains (losses) - derivatives, gross	(116,663,000)	(97,445,000)		(194,340,000)	(145,354,000)
Derivatives not designated as hedging instruments | Interest rate futures
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(3,371,000)	144,182,000		32,419,000	147,550,000
Notional Amount, Other long-term investments							615,445,000
Fair Value, Other long-term investments							6,393,000
Notional Amount, Other liabilities	435,998,000			435,998,000			270,019,000
Fair Value, Other liabilities	3,124,000			3,124,000			1,148,000
Derivatives not designated as hedging instruments | Equity futures
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(17,324,000)	11,524,000		(42,643,000)	(7,822,000)
Realized investment gains (losses) - derivatives, gross	17,300,000			42,600,000
Notional Amount, Other long-term investments	179,074,000			179,074,000			49,631,000
Fair Value, Other long-term investments	3,814,000			3,814,000			837,000
Notional Amount, Other liabilities	89,311,000			89,311,000			189,765,000
Fair Value, Other liabilities	62,000			62,000			1,454,000
Derivatives not designated as hedging instruments | Currency future
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(3,078,000)	2,376,000		(2,298,000)	2,177,000
Notional Amount, Other long-term investments							57,912,000
Fair Value, Other long-term investments							976,000
Notional Amount, Other liabilities	128,689,000			128,689,000			14,348,000
Fair Value, Other liabilities	1,261,000			1,261,000			126,000
Derivatives not designated as hedging instruments | Volatility futures
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	100,000			100,000
Derivatives not designated as hedging instruments | Volatility swaps
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(5,840,000)	3,495,000		(6,660,000)	(239,000)
Notional Amount, Other liabilities	2,675,000			2,675,000
Fair Value, Other liabilities	6,660,000			6,660,000
Derivatives not designated as hedging instruments | Equity options
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(9,184,000)	30,072,000		(29,903,000)	22,813,000
Notional Amount, Other long-term investments	503,094,000			503,094,000			440,000,000
Fair Value, Other long-term investments	54,291,000			54,291,000			19,396,000
Derivatives not designated as hedging instruments | Interest rate swaptions
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	(3,019,000)			2,293,000
Notional Amount, Other long-term investments	400,000,000			400,000,000
Fair Value, Other long-term investments	15,923,000			15,923,000
Derivatives not designated as hedging instruments | Interest rate swaps
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	6,361,000	5,808,000		10,187,000	5,808,000
Realized investment gains (losses) - derivatives, gross	199,000	(8,185,000)		(680,000)	(10,642,000)
Notional Amount, Other long-term investments	575,000,000			575,000,000			125,000,000
Fair Value, Other long-term investments	14,251,000			14,251,000			5,118,000
Notional Amount, Other liabilities	300,000,000			300,000,000			25,000,000
Fair Value, Other liabilities	6,489,000			6,489,000			3,064,000
Derivatives not designated as hedging instruments | Credit default swaps
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross		(23,897,000)			(22,981,000)
Derivatives not designated as hedging instruments | Interest support and YRT premium support agreements
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross	17,559,000	50,000		18,059,000	(402,000)
Notional Amount, Other long-term investments	798,444,000			798,444,000			796,713,000
Fair Value, Other long-term investments	24,459,000			24,459,000			6,400,000
Derivatives not designated as hedging instruments | Embedded derivative - Modco reinsurance treaties
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross	(101,999,000)	(109,542,000)		(139,972,000)	(130,914,000)
Notional Amount, Other long-term investments	30,299,000			30,299,000			30,001,000
Fair Value, Other long-term investments	1,794,000			1,794,000			2,038,000
Notional Amount, Other liabilities	2,681,689,000			2,681,689,000			2,761,686,000
Fair Value, Other liabilities	419,526,000			419,526,000			279,799,000
Derivatives not designated as hedging instruments | Embedded derivative - GMWB
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives related to variable annuity contracts, gross	2,921,000	(150,125,000)		(32,369,000)	(147,550,000)
Notional Amount, Other long-term investments	1,220,046,000			1,220,046,000			826,790,000
Fair Value, Other long-term investments	19,306,000			19,306,000			10,665,000
Notional Amount, Other liabilities	5,035,351,000			5,035,351,000			3,741,688,000
Fair Value, Other liabilities	198,823,000			198,823,000			157,813,000
Derivatives not designated as hedging instruments | Interest rate caps
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross	(143,000)	(2,581,000)		(2,658,000)	(2,581,000)
Notional Amount, Other long-term investments	3,000,000,000			3,000,000,000			3,000,000,000
Fair Value, Other long-term investments	9,000			9,000			2,666,000
Derivatives not designated as hedging instruments | Other
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross	255,000	(622,000)		17,000	(571,000)
Notional Amount, Other long-term investments	224,000			224,000			224,000
Fair Value, Other long-term investments	174,000			174,000			155,000
Derivatives not designated as hedging instruments | Interest Support Agreement
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross					400,000
Derivatives not designated as hedging instruments | YRT Premium support agreement
Notional amount and fair value of the entity's derivative financial instruments
Realized investment gains (losses) - derivatives, gross	17,600,000			18,100,000
Cash flow hedges | Inflation
Notional amount and fair value of the entity's derivative financial instruments
Notional Amount, Other long-term investments							7,068,000
Fair Value, Other long-term investments							1,000
Notional Amount, Other liabilities	188,947,000			188,947,000			244,399,000
Fair Value, Other liabilities	4,481,000			4,481,000			8,863,000
Cash flow hedges | Interest rate swaps
Notional amount and fair value of the entity's derivative financial instruments
Notional Amount, Other liabilities							75,000,000
Fair Value, Other liabilities							$ 3,443,000

[1] Recast from previously reported information