SUMMARY OF INVESTMENTS (Net Realized Investment Gains and Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	$ (20,179)	$ 4,055	$ 4,947
AVAILABLE-FOR-SALE
Proceeds from sales	132,250
Proceeds from sales	132,250	7,404	1,968
Gross realized gains	140	1,046	920
Gross realized losses	517	(20)	0
Discontinued Operations
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(1,057)	4,008	1,156
AVAILABLE-FOR-SALE
Proceeds from sales	0
Proceeds from sales		7,315	12,354
Gross realized gains	0	1,264	65
Gross realized losses	0	(78)	(639)
Continuing and Discontinuing Operations
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(21,236)	8,063	6,103
Fixed maturities \| Available-for-sale
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(254)	829	1,004
Fixed maturities \| Change in fair value
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(296)	924	189
Fixed maturities \| Sales
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	1,226	244	931
Equity securities
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(20,292)	1,942	2,654
Mortgage loans
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(46)	0	0
Cash equivalents
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	0	0	169
Real Estate
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	$ (517)	$ 116	$ 0

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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