INVESTMENTS - Investments held to maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investments
Amortized Cost	$ 5,066	$ 5,027
Unrealized Gains	72	81
Unrealized Losses	(44)
Fair Value	5,094	5,108
Corporate Bonds
Investments
Amortized Cost	4,588	4,691
Unrealized Gains	72	81
Unrealized Losses	(44)
Fair Value	4,616	4,772
US Treasury Bill
Investments
Amortized Cost	100
Fair Value	100
Money Market & CD’s
Investments
Amortized Cost	378	336
Fair Value	$ 378	$ 336

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

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