INVESTMENTS - Investments held to maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Investments
Amortized Cost	$ 5,027	$ 4,921
Unrealized Gains	81	2
Unrealized Losses		(1)
Fair Value	5,108	4,922
Corporate Bonds
Investments
Amortized Cost	4,691	2,164
Unrealized Gains	81	2
Unrealized Losses		(1)
Fair Value	4,772	2,165
Money Market & CD’s
Investments
Amortized Cost	336	2,757
Fair Value	$ 336	$ 2,757

Amount of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section 50
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