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.

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REVENUE - Property Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue
Revenue	$ 142,589	$ 136,437	$ 447,829	$ 378,853
Stream interests
Disaggregation of Revenue
Revenue	95,346	97,460	309,568	274,065
Stream interests \| Mount Milligan
Disaggregation of Revenue
Revenue	33,803	32,298	113,135	93,423
Stream interests \| Pueblo Viejo
Disaggregation of Revenue
Revenue	30,173	28,302	88,998	73,534
Stream interests \| Andacollo
Disaggregation of Revenue
Revenue	13,022	22,055	54,297	63,324
Stream interests \| Wassa and Prestea
Disaggregation of Revenue
Revenue	8,774	8,647	24,644	18,760
Stream interests \| Other
Disaggregation of Revenue
Revenue	9,574	6,158	28,494	25,024
Royalty interests
Disaggregation of Revenue
Revenue	47,243	38,977	138,261	104,788
Royalty interests \| Other
Disaggregation of Revenue
Revenue	25,506	25,152	79,551	71,257
Royalty interests \| Penasquito
Disaggregation of Revenue
Revenue	13,128	7,425	36,289	19,422
Royalty interests \| Cortez
Disaggregation of Revenue
Revenue	$ 8,609	$ 6,400	$ 22,421	$ 14,109