SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) segment	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Long Lived Assets and Pre-Tax Income by Geographical Information
Number of reportable segments | segment			2
Stream and royalty interest	$ 3,115,580		$ 3,115,580		$ 3,237,402
Revenue	138,617	$ 131,429	453,051	$ 440,226
Cost of sales	21,351	23,221	69,738	69,670
Production taxes	1,671	1,119	4,934	4,765
Depletion	39,989	37,639	124,501	129,368
Total segment gross profit	75,606	69,450	253,878	236,423
Canada
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	1,089,598		1,089,598		1,132,506
Africa
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	271,133		271,133		300,043
Dominican Republic
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	312,805		312,805		320,867
Chile
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	450,482		450,482		460,428
United States
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	803,523		803,523		823,203
Australia
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	21,547		21,547		22,120
Mexico
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	44,035		44,035		50,156
Rest of world
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	122,457		122,457		128,079
Stream interests
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	1,379,201		1,379,201		1,470,298
Revenue	98,978	98,732	319,982	308,863
Cost of sales	21,351	23,221	69,738	69,670
Depletion	30,433	32,576	93,537	106,745
Total segment gross profit	47,194	42,935	156,707	132,448
Stream interests | Canada
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	473,399		473,399		511,957
Revenue	42,577	46,861	150,405	152,938
Stream interests | Africa
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	270,812		270,812		299,722
Revenue	18,092	13,257	54,394	38,633
Stream interests | Dominican Republic
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	312,805		312,805		320,867
Revenue	16,688	21,156	62,586	64,232
Stream interests | Chile
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	226,366		226,366		236,312
Revenue	14,644	12,170	35,401	39,566
Stream interests | Rest of world
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	95,819		95,819		101,440
Revenue	6,977	5,288	17,196	13,494
Royalty interests
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	1,736,379		1,736,379		1,767,104
Revenue	39,639	32,697	133,069	131,363
Production taxes	1,671	1,119	4,934	4,765
Depletion	9,556	5,063	30,964	22,623
Total segment gross profit	28,412	26,515	97,171	103,975
Royalty interests | Canada
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	616,199		616,199		620,549
Revenue	3,090	4,826	9,585	21,377
Royalty interests | Africa
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	321		321		321
Revenue				430
Royalty interests | Chile
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	224,116		224,116		224,116
Royalty interests | United States
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	803,523		803,523		823,203
Revenue	28,237	11,413	85,082	52,616
Royalty interests | Australia
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	21,547		21,547		22,120
Revenue	4,696	3,446	13,874	11,533
Royalty interests | Mexico
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	44,035		44,035		50,156
Revenue	1,964	11,095	19,413	38,915
Royalty interests | Rest of world
Long Lived Assets and Pre-Tax Income by Geographical Information
Stream and royalty interest	26,638		26,638		$ 26,639
Revenue	$ 1,652	$ 1,917	$ 5,115	$ 6,492