ROYALTY INTERESTS IN MINERAL PROPERTIES (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Jun. 30, 2012
Royalty interests in mineral properties
Cost	$ 2,277,704	$ 2,158,870
Restructuring		(1,328)
Accumulated Depletion	(288,012)	(266,554)
Net	1,989,692	1,890,988
Production stage royalty interests
Royalty interests in mineral properties
Cost	1,094,854	1,090,124
Accumulated Depletion	(288,012)	(266,554)
Net	806,842	823,570
Production stage royalty interests | Andacollo
Royalty interests in mineral properties
Cost	272,998	272,998
Accumulated Depletion	(31,384)	(27,345)
Net	241,614	245,653
Production stage royalty interests | Voisey's Bay
Royalty interests in mineral properties
Cost	150,138	150,138
Accumulated Depletion	(38,466)	(33,192)
Net	111,672	116,946
Production stage royalty interests | Penasquito
Royalty interests in mineral properties
Cost	99,172	99,172
Accumulated Depletion	(10,225)	(9,075)
Net	88,947	90,097
Production stage royalty interests | Las Cruces
Royalty interests in mineral properties
Cost	57,230	57,230
Accumulated Depletion	(8,113)	(6,499)
Net	49,117	50,731
Production stage royalty interests | Mulatos
Royalty interests in mineral properties
Cost	48,092	48,092
Accumulated Depletion	(19,852)	(18,721)
Net	28,240	29,371
Production stage royalty interests | Wolverine
Royalty interests in mineral properties
Cost	45,158	45,158
Accumulated Depletion	(2,686)	(1,625)
Net	42,472	43,533
Production stage royalty interests | Dolores
Royalty interests in mineral properties
Cost	44,878	44,878
Accumulated Depletion	(6,484)	(6,021)
Net	38,394	38,857
Production stage royalty interests | Canadian Malartic
Royalty interests in mineral properties
Cost	38,800	38,800
Accumulated Depletion	(4,079)	(3,292)
Net	34,721	35,508
Production stage royalty interests | Gwalia Deeps
Royalty interests in mineral properties
Cost	31,070	28,119
Accumulated Depletion	(4,959)	(4,398)
Net	26,111	23,721
Production stage royalty interests | Holt
Royalty interests in mineral properties
Cost	25,428	25,428
Accumulated Depletion	(3,772)	(2,980)
Net	21,656	22,448
Production stage royalty interests | Inata
Royalty interests in mineral properties
Cost	24,871	24,871
Accumulated Depletion	(7,684)	(7,320)
Net	17,187	17,551
Production stage royalty interests | Leeville
Royalty interests in mineral properties
Cost	18,322	18,322
Accumulated Depletion	(14,844)	(14,436)
Net	3,478	3,886
Production stage royalty interests | Robinson
Royalty interests in mineral properties
Cost	17,825	17,825
Accumulated Depletion	(10,199)	(9,872)
Net	7,626	7,953
Production stage royalty interests | Cortez
Royalty interests in mineral properties
Cost	10,630	10,630
Accumulated Depletion	(9,687)	(9,673)
Net	943	957
Production stage royalty interests | Other
Royalty interests in mineral properties
Cost	210,242	208,463
Accumulated Depletion	(115,578)	(112,105)
Net	94,664	96,358
Development stage royalty interests
Royalty interests in mineral properties
Cost	986,891	868,070
Restructuring		(1,328)
Net	986,891	866,742
Development stage royalty interests | Other
Royalty interests in mineral properties
Cost	38,694	40,022
Restructuring		(1,328)
Net	38,694	38,694
Development stage royalty interests | Pascua-Lama
Royalty interests in mineral properties
Cost	372,105	372,105
Net	372,105	372,105
Development stage royalty interests | Mt. Milligan
Royalty interests in mineral properties
Cost	576,092	455,943
Net	576,092	455,943
Exploration stage royalty interests
Royalty interests in mineral properties
Cost	195,959	200,676
Net	$ 195,959	$ 200,676