STREAM AND ROYALTY INTERESTS, NET (Details) $ in Thousands		6 Months Ended
	Oct. 01, 2020 oz	Dec. 31, 2020 USD ($) oz	Jun. 30, 2020 USD ($)
Stream and royalty interests, net | $		$ 2,231,980	$ 2,318,913
Wassa and Prestea
Stream and royalty interests, net | $		$ 73,600
Wassa | Initial Royalty
Gold streaming interest (as a percent)	10.50%
Gold delivered (in ounces) | oz	240,000
Spot price paid (as a percent)	20.00%
Remaining gold to be delivered (in ounces) | oz		110,200
Wassa | Subsequent Royalty
Gold streaming interest (as a percent)	5.50%
Spot price paid (as a percent)	30.00%
Prestea/Bogoso
Gold streaming interest (as a percent)	5.50%
Spot price paid (as a percent)	30.00%