INVESTMENT SECURITIES (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	$ 27,748	$ 26,943
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	45	2
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	0	10
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	27,793	26,935
Short-term Investments [Member] \| US Government Agencies Debt Securities [Member]
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	27,748	26,943
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	45	2
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	0	10
Obligations of domestic governmental agencies (maturing between July 2019 and June 2020) (held-to-maturity)	$ 27,793	$ 26,935

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
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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Balance Type:	debit
Period Type:	instant

- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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- Definition

Amount of unrealized holding gain before loss recognized in the income statement for investments in trading securities.

+ References

No definition available.

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Balance Type:	credit
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- Definition

Amount of unrealized holding loss before gain recognized in the income statement for investments in trading securities.

+ References

No definition available.

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Namespace Prefix:	us-gaap_
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- Details

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