INVESTMENTS (Major Categories of Investment Gains and Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	$ (990)	$ 2,120
Gains (losses) on trading securities	(25)	3
Other-than-temporary impairments	(238)	0
Realized gains on fixed maturities
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	121	10
Change in fair value of equity securities
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	(599)	126
Change in surrender value of company owned life insurance
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	(251)	189
Realized gain on company owned life insurance
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	0	1,792
Other gains principally real estate
Gain (Loss) on Securities [Line Items]
Net investment gains (losses)	$ 2	$ 0

Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 14
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 320
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