ROYALTY AND STREAM INTERESTS (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Royalty and stream interests
Cost			$ 2,647,976	$ 2,551,727
Accumulated Depletion			(536,029)	(442,660)
Impairments			(28,339)
Total royalty and stream interest, net			2,083,608	2,109,067
Impairments			28,339
Royalty Receivables			37,681	46,654
Return of advance payment			10,000
Prepaid expenses and other			3,798	7,840
Other
Royalty and stream interests
Impairments			2,372
Wolverine
Royalty and stream interests
Total royalty and stream interest, net			5,300
Impairments			$ 25,967
Royalty Receivables	$ 3,000
Allowance for royalty receivables	3,000
Wolverine | Minimum
Royalty and stream interests
Percentage of royalty interests acquired			0.00%
Wolverine | Maximum
Royalty and stream interests
Percentage of royalty interests acquired			9.445%
Tulsequah
Royalty and stream interests
Material properties net related to investments		$ 10,000
Material properties net direct acquisition costs		600
Total royalty and stream interest, net	0
Impairments	$ 600
Chieftain
Royalty and stream interests
Return of advance payment			$ 10,000
Production Stage Royalty Interest
Royalty and stream interests
Cost			1,129,230	1,121,776
Accumulated Depletion			(500,834)	(434,919)
Impairments			(27,586)
Total royalty and stream interest, net			600,810	686,857
Production Stage Royalty Interest | Andacollo
Royalty and stream interests
Cost			272,998	272,998
Accumulated Depletion			(65,467)	(56,147)
Total royalty and stream interest, net			207,531	216,851
Production Stage Royalty Interest | Voisey's Bay
Royalty and stream interests
Cost			150,138	150,138
Accumulated Depletion			(76,141)	(67,377)
Total royalty and stream interest, net			73,997	82,761
Production Stage Royalty Interest | Penasquito
Royalty and stream interests
Cost			99,172	99,172
Accumulated Depletion			(24,555)	(17,801)
Total royalty and stream interest, net			74,617	81,371
Production Stage Royalty Interest | Mulatos
Royalty and stream interests
Cost			48,092	48,092
Accumulated Depletion			(32,313)	(28,548)
Total royalty and stream interest, net			15,779	19,544
Production Stage Royalty Interest | Holt
Royalty and stream interests
Cost			34,612	34,612
Accumulated Depletion			(13,950)	(10,474)
Total royalty and stream interest, net			20,662	24,138
Production Stage Royalty Interest | Robinson
Royalty and stream interests
Cost			17,825	17,825
Accumulated Depletion			(12,748)	(11,887)
Total royalty and stream interest, net			5,077	5,938
Production Stage Royalty Interest | Cortez
Royalty and stream interests
Cost			10,630	10,630
Accumulated Depletion			(9,933)	(9,772)
Total royalty and stream interest, net			697	858
Production Stage Royalty Interest | Other
Royalty and stream interests
Cost			495,763	488,309
Accumulated Depletion			(265,727)	(232,913)
Impairments			(27,586)
Total royalty and stream interest, net			202,450	255,396
Production Stage Stream Interests | Mt. Milligan
Royalty and stream interests
Cost			783,046	783,046
Accumulated Depletion			(35,195)	(7,741)
Total royalty and stream interest, net			747,851	775,305
Production Stage Royalty and Stream Interests
Royalty and stream interests
Cost			1,912,276	1,904,822
Accumulated Depletion			(536,029)	(442,660)
Impairments			(27,586)
Total royalty and stream interest, net			1,348,661	1,462,162
Development Stage Royalty Interest
Royalty and stream interests
Cost			439,122	441,593
Total royalty and stream interest, net			439,122	441,593
Development Stage Royalty Interest | Other
Royalty and stream interests
Cost			67,017	69,488
Total royalty and stream interest, net			67,017	69,488
Development Stage Royalty Interest | Pascua Lama
Royalty and stream interests
Cost			372,105	372,105
Total royalty and stream interest, net			372,105	372,105
Development Stage Stream Interest
Royalty and stream interests
Cost			84,026	41,103
Impairments			(603)
Total royalty and stream interest, net			83,423	41,103
Development Stage Stream Interest | Other
Royalty and stream interests
Cost			8,183	10,483
Impairments			(603)
Total royalty and stream interest, net			7,580	10,483
Development Stage Stream Interest | Phoenix Gold
Royalty and stream interests
Cost			75,843	30,620
Total royalty and stream interest, net			75,843	30,620
Development Stage Royalty and Stream Interest
Royalty and stream interests
Cost			523,148	482,696
Impairments			(603)
Total royalty and stream interest, net			522,545	482,696
Exploration Stage Royalty Interest
Royalty and stream interests
Cost			212,552	164,209
Impairments			(150)
Total royalty and stream interest, net			$ 212,402	$ 164,209
Production Stage and Exploration Stage Royalty Interest
Royalty and stream interests
Impairments		$ 1,800