ROYALTY INTERESTS IN MINERAL PROPERTIES (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Jun. 30, 2011
Royalty interests in mineral properties
Cost	$ 2,075,848	$ 1,882,186
Restructuring	(1,328)
Accumulated Depletion	(249,955)	(191,747)
Net	1,824,565	1,690,439
Production stage royalty interests
Royalty interests in mineral properties
Cost	1,065,660	1,054,539
Accumulated Depletion	(249,955)	(191,747)
Net	815,705	862,792
Production stage royalty interests | Andacollo
Royalty interests in mineral properties
Cost	272,998	272,998
Accumulated Depletion	(24,327)	(13,076)
Net	248,671	259,922
Production stage royalty interests | Voisey's Bay
Royalty interests in mineral properties
Cost	150,138	150,138
Accumulated Depletion	(30,155)	(15,526)
Net	119,983	134,612
Production stage royalty interests | Penasquito
Royalty interests in mineral properties
Cost	99,172	99,172
Accumulated Depletion	(8,142)	(5,457)
Net	91,030	93,715
Production stage royalty interests | Las Cruces
Royalty interests in mineral properties
Cost	57,230	57,230
Accumulated Depletion	(5,194)	(2,615)
Net	52,036	54,615
Production stage royalty interests | Mulatos
Royalty interests in mineral properties
Cost	48,092	48,092
Accumulated Depletion	(17,490)	(14,199)
Net	30,602	33,893
Production stage royalty interests | Wolverine
Royalty interests in mineral properties
Cost	45,158	45,158
Accumulated Depletion	(897)	(257)
Net	44,261	44,901
Production stage royalty interests | Dolores
Royalty interests in mineral properties
Cost	44,878	44,878
Accumulated Depletion	(5,651)	(4,005)
Net	39,227	40,873
Production stage royalty interests | Canadian Malartic
Royalty interests in mineral properties
Cost	38,800	38,800
Accumulated Depletion	(2,505)	(367)
Net	36,295	38,433
Production stage royalty interests | Gwalia Deeps
Royalty interests in mineral properties
Cost	28,119	22,854
Accumulated Depletion	(3,587)	(1,715)
Net	24,532	21,139
Production stage royalty interests | Holt
Royalty interests in mineral properties
Cost	25,428	25,428
Accumulated Depletion	(2,275)	(620)
Net	23,153	24,808
Production stage royalty interests | Inata
Royalty interests in mineral properties
Cost	24,871	24,871
Accumulated Depletion	(6,942)	(5,158)
Net	17,929	19,713
Production stage royalty interests | Leeville
Royalty interests in mineral properties
Cost	18,322	18,322
Accumulated Depletion	(14,216)	(12,920)
Net	4,106	5,402
Production stage royalty interests | Robinson
Royalty interests in mineral properties
Cost	17,825	17,825
Accumulated Depletion	(9,579)	(8,827)
Net	8,246	8,998
Production stage royalty interests | Cortez
Royalty interests in mineral properties
Cost	10,630	10,630
Accumulated Depletion	(9,659)	(9,619)
Net	971	1,011
Production stage royalty interests | Other
Royalty interests in mineral properties
Cost	183,999	178,143
Accumulated Depletion	(109,336)	(97,386)
Net	74,663	80,757
Development stage royalty interests
Royalty interests in mineral properties
Cost	818,995	625,951
Restructuring	(1,328)
Net	817,667	625,951
Development stage royalty interests | Other
Royalty interests in mineral properties
Cost	35,947	26,250
Restructuring	(1,328)
Net	34,619	26,250
Development stage royalty interests | Mt. Milligan
Royalty interests in mineral properties
Cost	410,943	227,596
Net	410,943	227,596
Development stage royalty interests | Pascua-Lama
Royalty interests in mineral properties
Cost	372,105	372,105
Net	372,105	372,105
Exploration stage royalty interests
Royalty interests in mineral properties
Cost	191,193	201,696
Net	$ 191,193	$ 201,696