MAJOR SOURCES OF REVENUE (Details) - Sales Revenue, Services, Net - Customer Concentration Risk - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Thompson Creek
Major sources of revenue
Revenue	$ 125,438	$ 94,104	$ 27,209
Percentage of total revenue	34.90%	33.80%	11.50%
Barrick
Major sources of revenue
Revenue	$ 49,683	$ 24,849	$ 19,456
Percentage of total revenue	13.80%	8.90%	8.20%
Teck
Major sources of revenue
Revenue	$ 49,243	$ 38,033	$ 48,777
Percentage of total revenue	13.70%	13.70%	20.60%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

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