INVESTMENTS (Summary of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Investment Income, Interest and Dividend [Abstract]
Interest income	$ 2,887	$ 2,169
Dividends income	56	149
Net investment income	$ 2,943	$ 2,318

Amount of dividend income on nonoperating securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Period Type:	duration

- References

No definition available.

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