INVESTMENTS (Summary of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Investment Income, Interest and Dividend [Abstract]
Interest income	$ 4,169	$ 2,927	$ 7,826	$ 5,815
Dividends income	90	51	143	106
Net investment income	$ 4,259	$ 2,978	$ 7,969	$ 5,921

Amount of dividend income on nonoperating securities.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

+ Details

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

+ References

+ Details

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- References

No definition available.

+ Details

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