INCOME TAXES (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Effective income tax rate related to continuing operations
Statutory federal income tax rate applied to pre-tax income (as a percent)	35.00%	35.00%	35.00%
State income taxes (as a percent)	0.30%	0.40%	0.50%
Investment income not subject to tax (as a percent)	(3.10%)	(2.20%)	(1.60%)
Uncertain tax positions (as a percent)	0.40%		(1.30%)
Other (as a percent)	0.60%	(0.30%)	0.20%
Effective tax rate (as a percent)	33.20%	32.90%	32.80%
Income tax expense per the income tax returns:
Federal	$ 72,743,000	$ 9,510,000	$ (6,723,000)
State	3,443,000	264,000	3,509,000
Total current	76,186,000	9,774,000	(3,214,000)
Deferred income tax expense:
Federal	71,659,000	142,761,000	115,172,000
State	2,674,000	2,304,000	(2,055,000)
Total deferred	74,333,000	145,065,000	113,117,000
Deferred income tax assets:
Premium receivables and policy liabilities	56,918,000	35,432,000
Invested assets (other than unrealized gains)		60,524,000
Deferred compensation	78,465,000	72,944,000
U.S. capital loss carryforwards		4,763,000
Other	52,158,000	7,049,000
Valuation allowance	(4,653,000)	(2,593,000)
Deferred income tax	182,888,000	178,119,000
Deferred income tax liabilities:
Deferred policy acquisition costs and value of business acquired	916,406,000	872,297,000
Invested assets (other than unrealized gains)	28,396,000
Unrealized gain on investments	974,475,000	566,451,000
Deferred income tax liabilities	1,919,277,000	1,438,748,000
Net deferred income tax liability	(1,736,389,000)	(1,260,629,000)
State operating loss carryforwards, valuation allowance	4,600,000	2,600,000
Unfavorable change in valuation allowance, net of federal income taxes	$ 1,300,000