REVENUE - Property Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue
Revenue	$ 174,431	$ 146,880
Stream interests
Disaggregation of Revenue
Revenue	115,921	106,503
Stream interests | Mount Milligan
Disaggregation of Revenue
Revenue	53,455	34,620
Stream interests | Pueblo Viejo
Disaggregation of Revenue
Revenue	27,198	31,270
Stream interests | Andacollo
Disaggregation of Revenue
Revenue	11,601	23,509
Stream interests | Wassa
Disaggregation of Revenue
Revenue	8,033	9,108
Stream interests | Khoemacau
Disaggregation of Revenue
Revenue	107
Stream interests | Other
Disaggregation of Revenue
Revenue	15,527	7,996
Royalty interests
Disaggregation of Revenue
Revenue	58,510	40,377
Royalty interests | Cortez
Disaggregation of Revenue
Revenue	17,101	5,684
Royalty interests | Penasquito
Disaggregation of Revenue
Revenue	12,212	10,209
Royalty interests | Other
Disaggregation of Revenue
Revenue	$ 29,197	$ 24,484