REVENUE - Property Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue
Revenue	$ 144,042	$ 146,441	$ 314,434	$ 308,796
Stream interests
Disaggregation of Revenue
Revenue	106,015	104,879	221,005	210,130
Stream interests | Mt. Milligan
Disaggregation of Revenue
Revenue	41,208	45,627	87,863	88,043
Stream interests | Pueblo Viejo
Disaggregation of Revenue
Revenue	23,540	19,812	45,898	43,076
Stream interests | Khoemacau
Disaggregation of Revenue
Revenue	8,881	5,202	18,035	7,591
Stream interests | Andacollo
Disaggregation of Revenue
Revenue	7,823	11,721	20,757	27,395
Stream interests | Other interest
Disaggregation of Revenue
Revenue	24,563	22,517	48,452	44,025
Royalty interests
Disaggregation of Revenue
Revenue	38,027	41,562	93,429	98,666
Royalty interests | Cortez Legacy Zone
Disaggregation of Revenue
Revenue	14,305	8,138	37,393	24,852
Royalty interests | Cortez CC Zone
Disaggregation of Revenue
Revenue	3,520		6,726
Royalty interests | Penasquito
Disaggregation of Revenue
Revenue	6,105	9,664	13,538	22,758
Royalty interests | Other interest
Disaggregation of Revenue
Revenue	$ 14,097	$ 23,760	$ 35,772	$ 51,056