COMPOSITION OF CERTAIN FINANCIAL STATEMENT ITEMS (Marketable Equity Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Marketable equity securities	$ 3,398	$ 2,220

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))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant