INVESTMENTS - Disposition of Fixed Securities and Equities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt securities | Available for sale securities | SALES
Summary of the disposition of fixed maturities and equities
Proceeds From Sales	$ 394,318	$ 169,002	$ 329,091
Gross Realized Gains	3,131	2,406	7,158
Gross Realized Losses	(5,349)	(1,670)	(3,287)
Marketable Securities, Realized Gain (Loss), Excluding Other than Temporary Impairments, Total	(2,218)	736	3,871
Debt securities | Available for sale securities | CALLS/MATURITIES
Summary of the disposition of fixed maturities and equities
Proceeds From Sales	187,380	195,617	141,255
Gross Realized Gains	311	262	445
Gross Realized Losses	(111)	(139)	(2)
Marketable Securities, Realized Gain (Loss), Excluding Other than Temporary Impairments, Total	200	123	443
Equity securities | SALES
Summary of the disposition of fixed maturities and equities
Proceeds From Sales	147,838	36,573	89,909
Gross Realized Gains	71,065	13,178	39,668
Gross Realized Losses	(1,197)	(2,896)	(959)
Marketable Securities, Realized Gain (Loss), Excluding Other than Temporary Impairments, Total	$ 69,868	$ 10,282	$ 38,709