SUMMARY OF INVESTMENTS (Net Realized Investment Gains and Losses) (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	$ (32,395,000)	$ 53,779,000	$ (20,179,000)
AVAILABLE-FOR-SALE
Proceeds from sales	50,744,000	41,760,000	132,250,000
Gross realized gains	1,400,000	302,000	140,000
Gross realized losses	(495,000)	(13,000)	(517,000)
Continuing Operations
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(32,395,000)	53,779,000	(20,179,000)
Discontinued Operations
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	0	0	(1,057,000)
AVAILABLE-FOR-SALE
Proceeds from sales	0	0	0
Continuing and Discontinued Operations
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(32,395,000)	53,779,000	(21,236,000)
Fixed maturities \| Available-for-sale
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	1,787,000	655,000	(254,000)
Fixed maturities \| Allowance for credit losses
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(5,000)	0	0
Fixed maturities \| Change in fair value
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(3,314,000)	1,351,000	(296,000)
Fixed maturities \| Sales
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	2,950,000	1,993,000	1,226,000
Equity securities \| Change in fair value
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(6,875,000)	51,231,000	(21,994,000)
Equity securities \| Sales
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(26,906,000)	725,000	1,702,000
Mortgage loans on real estate
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	(4,000)	(26,000)	(46,000)
Real Estate
Gain (Loss) on Securities [Line Items]
Net realized investment gains (losses) from continuing operations	$ (28,000)	$ (2,150,000)	$ (517,000)

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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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