STREAM AND ROYALTY INTERESTS, NET - Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jun. 30, 2020
Cost	$ 3,533,204	$ 3,553,950
Accumulated Depletion	(1,308,769)	(1,233,696)
Impairments		(1,341)
Net	2,224,435	2,318,913
Other
Cost		137,826
Net		137,826
Total production stage stream and royalty interests
Cost	2,939,891	3,018,837
Accumulated Depletion	(1,308,769)	(1,233,696)
Impairments		(1,341)
Net	1,631,122	1,783,800
Production stage stream interests
Cost	2,111,423	2,111,423
Accumulated Depletion	(757,553)	(645,705)
Net	1,353,870	1,465,718
Production stage stream interests | Mount Milligan
Cost	790,635	790,635
Accumulated Depletion	(283,660)	(236,352)
Net	506,975	554,283
Production stage stream interests | Pueblo Viejo
Cost	610,404	610,404
Accumulated Depletion	(235,169)	(203,935)
Net	375,235	406,469
Production stage stream interests | Andacollo
Cost	388,182	388,182
Accumulated Depletion	(124,225)	(110,521)
Net	263,957	277,661
Production stage stream interests | Rainy River
Cost	175,727	175,727
Accumulated Depletion	(38,368)	(27,278)
Net	137,359	148,449
Production stage stream interests | Wassa
Cost	146,475	146,475
Accumulated Depletion	(76,131)	(67,619)
Net	70,344	78,856
Production stage royalty interests
Cost	828,468	907,414
Accumulated Depletion	(551,216)	(587,991)
Impairments		(1,341)
Net	277,252	318,082
Production stage royalty interests | Voisey's Bay
Cost	205,724	205,724
Accumulated Depletion	(107,225)	(101,381)
Net	98,499	104,343
Production stage royalty interests | Penasquito
Cost	99,172	99,172
Accumulated Depletion	(48,765)	(44,614)
Net	50,407	54,558
Production stage royalty interests | Cortez
Cost	80,681	80,681
Accumulated Depletion	(17,584)	(15,065)
Net	63,097	65,616
Production stage royalty interests | Other
Cost	442,891	521,837
Accumulated Depletion	(377,642)	(426,931)
Impairments		(1,341)
Net	65,249	93,565
Total development stage stream and royalty interests
Cost	298,330	219,597
Net	298,330	219,597
Development stage stream interests | Khoemacau
Cost	212,877	136,608
Net	212,877	136,608
Development stage stream interests | Other
Cost	12,037	12,037
Net	12,037	12,037
Development stage royalty interests
Cost		70,952
Net		70,952
Development stage royalty interests | Other
Cost	73,416	70,952
Net	73,416	70,952
Exploration stage royalty interests
Cost	294,983	315,516
Net	294,983	315,516
Exploration stage royalty interests | Pascua-Lama
Cost	177,690	177,690
Net	177,690	$ 177,690
Exploration stage royalty interests | Other
Cost	117,293
Net	$ 117,293