MARKETABLE EQUITY SECURITIES (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Marketable Securities
Fair value changes in equity securities	$ 1,418	$ (6,800)
Investment value	$ 17,900	$ 16,000
Contango
Marketable Securities
Investment shares owned (in shares)	809,744
Battle North Gold Corporation
Marketable Securities
Investment shares owned (in shares)	3,949,575
TriStar
Marketable Securities
Common stock that can be purchased by warrants (in shares)	19,640,000

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Balance held at close of period in number of shares.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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