OPERATING SEGMENTS (Details) (USD $)	3 Months Ended									12 Months Ended																		3 Months Ended	12 Months Ended			3 Months Ended	12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2012 Life Marketing	Dec. 31, 2011 Life Marketing	Dec. 31, 2010 Life Marketing	Dec. 31, 2012 Acquisitions	Dec. 31, 2011 Acquisitions	Dec. 31, 2010 Acquisitions	Dec. 31, 2012 Annuities	Dec. 31, 2011 Annuities	Dec. 31, 2010 Annuities	Dec. 31, 2012 Stable Value Products	Dec. 31, 2011 Stable Value Products	Dec. 31, 2010 Stable Value Products	Mar. 31, 2010 Asset Protection	Dec. 31, 2012 Asset Protection	Dec. 31, 2011 Asset Protection	Dec. 31, 2010 Asset Protection	Mar. 31, 2011 Corporate and Other	Dec. 31, 2012 Corporate and Other	Dec. 31, 2011 Corporate and Other	Dec. 31, 2010 Corporate and Other	Dec. 31, 2012 Adjustments	Dec. 31, 2011 Adjustments
Summarized financial information for the company's segments
Decrease in reserves related to final settlement in runoff line of business																												$ 7,800,000
Pre-tax earnings relating to settlement of a dispute																																8,500,000
Intersegment transactions amount										0		0		0
Revenues	823,070,000	864,196,000	867,039,000	901,755,000	842,684,000		898,499,000	866,375,000	801,027,000	3,456,060,000		3,408,585,000	[1]	2,936,984,000	[1]	1,233,654,000	1,193,927,000	1,127,924,000	1,064,295,000	982,821,000	761,344,000	610,489,000	633,185,000	500,697,000	123,274,000	170,455,000	168,127,000		294,146,000	282,587,000	269,597,000		130,202,000	145,610,000	109,295,000
Segment Operating Income (Loss)										462,165,000		413,533,000		332,763,000		102,114,000	96,110,000	123,495,000	171,060,000	157,393,000	111,143,000	117,778,000	79,373,000	48,109,000	60,329,000	56,780,000	39,207,000		9,765,000	16,892,000	24,267,000		1,119,000	6,985,000	(13,458,000)
Realized investment (losses) gains - investments										188,729,000		194,866,000		134,559,000
Realized investment (losses) gains - derivatives										(191,315,000)		(133,124,000)		(134,146,000)
Income tax expense	(34,615,000)	(35,778,000)	(35,438,000)	(45,212,000)	(30,160,000)		(39,579,000)	(48,557,000)	(33,223,000)	(151,043,000)		(151,519,000)	[1]	(109,865,000)	[1]
Net income	60,142,000	70,911,000	81,627,000	95,856,000	87,054,000		82,979,000	91,604,000	62,119,000	308,536,000	[1]	323,756,000	[1]	223,311,000	[1]
Realized gain (losses) on investments
Realized investment (losses) gains - investments, gross										174,692,000		200,432,000		117,056,000
Less: related amortization of DAC/VOBA										(14,037,000)		5,566,000		(17,503,000)
Realized investment (losses) gains - investments										188,729,000		194,866,000		134,559,000
Realized gain (losses) on derivatives
Realized investment gains (losses) - derivatives, gross										(227,816,000)		(155,005,000)	[1]	(144,438,000)	[1]
Less: settlements on certain interest rate swaps														168,000
Less: derivative activity related to certain annuities										(36,501,000)		(21,881,000)		(10,460,000)
Realized investment gains (losses) - derivatives										(191,315,000)		(133,124,000)		(134,146,000)
Net investment income	460,784,000	446,374,000	438,648,000	443,532,000	445,780,000		445,928,000	434,425,000	427,311,000	1,789,338,000		1,753,444,000	[1]	1,624,845,000	[1]	486,374,000	446,014,000	387,953,000	550,334,000	529,261,000	458,703,000	504,342,000	507,229,000	482,264,000	128,239,000	145,150,000	171,327,000		19,698,000	21,650,000	23,959,000		100,351,000	104,140,000	100,639,000
Amortization of deferred policy acquisition costs and value of business acquired										192,183,000		249,520,000	[1]	144,496,000	[1]	45,079,000	87,461,000	47,809,000	77,251,000	75,041,000	64,410,000	45,319,000	57,201,000	76,000	947,000	4,556,000	5,430,000		22,569,000	22,607,000	25,077,000		1,018,000	2,654,000	1,694,000
Other-than-temporary impairments										58,144,000		47,321,000	[1]	41,364,000	[1]
Operating Segment Assets
Investments and other assets	53,848,454,000				48,693,092,000					53,848,454,000		48,693,092,000				12,171,384,000	10,885,785,000		11,312,550,000	11,471,856,000		17,649,488,000	14,945,002,000		2,509,160,000	2,767,163,000			740,153,000	707,181,000			9,446,057,000	7,894,614,000		19,662,000	21,491,000
Deferred policy acquisition costs and value of business acquired	3,225,356,000				3,223,220,000	[1]				3,225,356,000		3,223,220,000	[1]	3,063,409,000		2,001,708,000	1,912,916,000	1,826,001,000	679,746,000	824,277,000	810,681,000	491,184,000	435,462,000	368,279,000	1,399,000	2,347,000	6,903,000		50,253,000	46,606,000	48,048,000		1,066,000	1,612,000	3,497,000
Goodwill	83,773,000				86,871,000	[1]				83,773,000		86,871,000	[1]	89,970,000					35,615,000	38,713,000	41,812,000								48,158,000	48,158,000	48,158,000
Total assets	$ 57,157,583,000				$ 52,003,183,000	[1]				$ 57,157,583,000		$ 52,003,183,000	[1]			$ 14,173,092,000	$ 12,798,701,000		$ 12,027,911,000	$ 12,334,846,000		$ 18,140,672,000	$ 15,380,464,000		$ 2,510,559,000	$ 2,769,510,000			$ 838,564,000	$ 801,945,000			$ 9,447,123,000	$ 7,896,226,000		$ 19,662,000	$ 21,491,000

[1] Recast from previously reported information