OPERATING SEGMENTS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Summarized financial information for the company's segments
Intersegment transactions amount	$ 0	$ 0
Revenues	885,583	901,755
Segment Operating Income (Loss)	103,141	141,307
Realized investment (losses) gains - investments	(9,857)	22,430
Realized investment (losses) gains - derivatives	16,530	(22,669)
Income tax expense	(35,936)	(45,212)
Net income	73,878	95,856
Realized gain (losses) on investments
Investment gains (losses)	(8,830)	16,887
Less: related amortization of DAC/VOBA	1,027	(5,543)
Realized investment gains (losses) in investments	(9,857)	22,430
Realized gain (losses) on derivatives
Derivative gains (losses)	3,607	(29,909)
Less: VA GMWB economic cost	(12,923)	(7,240)
Realized investment gains (losses) - derivatives	16,530	(22,669)
Other-than-temporary impairments	4,584	18,596
Operating Segment Assets
Investments and other assets	54,976,902		53,848,454
Deferred policy acquisition costs and value of business acquired	3,252,030		3,225,356
Goodwill	82,998		83,773
Total assets	58,311,930		57,157,583
Life Marketing
Summarized financial information for the company's segments
Revenues	338,679	315,506
Segment Operating Income (Loss)	23,477	29,997
Operating Segment Assets
Investments and other assets	12,426,547		12,171,384
Deferred policy acquisition costs and value of business acquired	2,045,332		2,001,708
Total assets	14,471,879		14,173,092
Acquisitions
Summarized financial information for the company's segments
Revenues	250,487	299,509
Segment Operating Income (Loss)	34,377	39,099
Operating Segment Assets
Investments and other assets	11,302,319		11,312,550
Deferred policy acquisition costs and value of business acquired	632,595		679,746
Goodwill	34,840		35,615
Total assets	11,969,754		12,027,911
Annuities
Summarized financial information for the company's segments
Revenues	164,353	139,062
Segment Operating Income (Loss)	42,869	35,459
Operating Segment Assets
Investments and other assets	18,498,392		17,649,488
Deferred policy acquisition costs and value of business acquired	522,122		491,184
Total assets	19,020,514		18,140,672
Stable Value Products
Summarized financial information for the company's segments
Revenues	31,920	34,656
Segment Operating Income (Loss)	17,844	12,646
Operating Segment Assets
Investments and other assets	2,543,291		2,509,160
Deferred policy acquisition costs and value of business acquired	1,318		1,399
Total assets	2,544,609		2,510,559
Asset Protection
Summarized financial information for the company's segments
Revenues	71,311	72,644
Segment Operating Income (Loss)	4,470	2,840
Operating Segment Assets
Investments and other assets	750,098		740,153
Deferred policy acquisition costs and value of business acquired	49,688		50,253
Goodwill	48,158		48,158
Total assets	847,944		838,564
Corporate and Other
Summarized financial information for the company's segments
Revenues	28,833	40,378
Segment Operating Income (Loss)	(19,896)	21,266
Operating Segment Assets
Investments and other assets	9,437,968		9,446,057
Deferred policy acquisition costs and value of business acquired	975		1,066
Total assets	9,438,943		9,447,123
Adjustments
Operating Segment Assets
Investments and other assets	18,287		19,662
Total assets	$ 18,287		$ 19,662