REVENUE - Metal Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue
Revenue	$ 146,880	$ 118,774
Stream interests
Disaggregation of Revenue
Revenue	106,503	86,981
Stream interests \| Gold
Disaggregation of Revenue
Revenue	83,597	72,224
Stream interests \| Silver
Disaggregation of Revenue
Revenue	10,898	8,436
Stream interests \| Copper
Disaggregation of Revenue
Revenue	12,008	6,321
Royalty interests
Disaggregation of Revenue
Revenue	40,377	31,793
Royalty interests \| Gold
Disaggregation of Revenue
Revenue	26,904	21,757
Royalty interests \| Silver
Disaggregation of Revenue
Revenue	3,441	1,829
Royalty interests \| Copper
Disaggregation of Revenue
Revenue	4,060	2,980
Royalty interests \| Other
Disaggregation of Revenue
Revenue	$ 5,972	$ 5,227

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details