SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 7) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Amount Reclassified from Accumulated Other Comprehensive Earnings
Net realized investment gains									$ 22,036	$ 26,528	$ 17,293
Other-than-temporary-impairment losses on investments										(1,156)	(257)
Earnings before income taxes	40,812	55,309	43,576	35,969	28,575	36,480	36,568	41,109	175,666	142,732	183,586
Income tax expense									(49,411)	(39,386)	(56,988)
Net earnings	33,859	37,647	29,902	24,847	25,097	25,463	24,748	28,038	126,255	103,346	126,598
Reclassifications out of accumulated other comprehensive earnings | Unrealized gains and losses on available-for-sale securities
Amount Reclassified from Accumulated Other Comprehensive Earnings
Net realized investment gains									22,871	29,209	17,021
Other-than-temporary-impairment losses on investments										(1,156)	(257)
Earnings before income taxes									22,871	28,053	16,764
Income tax expense									(8,005)	(9,819)	(5,867)
Net earnings									$ 14,866	$ 18,234	$ 10,897