COMPOSITION OF CERTAIN FINANCIAL STATEMENT ITEMS (Schedule of investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Marketable equity securities - short-term	$ 2,560	$ 1,711
Marketable equity securities - long-term	2,360	1,520
Total Marketable equity securities	$ 4,920	$ 3,231

Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(4))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Name Accounting Standards Codification
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