SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details 2) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2015 USD ($) $ / oz	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2015 USD ($) segment $ / oz	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)
Long Lived Assets and Pre-Tax Income by Geographical Information
Number of reportable segments | segment									2
Royalty and stream interests, net	$ 2,083,608				$ 2,109,067				$ 2,083,608	$ 2,109,067
Revenue	$ 73,579	$ 74,110	$ 61,304	$ 69,026	70,142	$ 57,748	$ 52,785	$ 56,487	278,019	237,162	$ 289,224
Cost of sales									33,450	9,158
Net Revenue									$ 244,569	228,004
Cost of Sales
Cash payment for each ounce of gold (in dollars per ounce) | $ / oz	435								435
Canada
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	$ 1,074,779				1,110,206				$ 1,074,779	1,110,206
Chile
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	653,019				662,482				653,019	662,482
Mexico
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	131,742				145,625				131,742	145,625
United States
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	110,286				68,889				110,286	68,889
Australia
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	50,119				55,241				50,119	55,241
Africa
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	12,760				15,226				12,760	15,226
Other.
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	50,903				51,398				50,903	51,398
Royalty Interest
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	1,252,334				1,292,659				1,252,334	1,292,659
Revenue									183,915	209,953	289,224
Net Revenue									183,915	209,953	289,224
Royalty Interest | Canada
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	251,688				293,798				251,688	293,798
Revenue									37,496	54,277	68,247
Net Revenue									37,496	54,277	68,247
Royalty Interest | Chile
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	653,019				662,482				653,019	662,482
Revenue									39,508	50,733	84,631
Net Revenue									39,508	50,733	84,631
Royalty Interest | Mexico
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	131,742				145,625				131,742	145,625
Revenue									43,008	43,093	53,550
Net Revenue									43,008	43,093	53,550
Royalty Interest | United States
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	110,286				68,889				110,286	68,889
Revenue									42,675	34,671	50,416
Net Revenue									42,675	34,671	50,416
Royalty Interest | Australia
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	50,119				55,241				50,119	55,241
Revenue									8,494	8,353	10,216
Net Revenue									8,494	8,353	10,216
Royalty Interest | Africa
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	12,760				15,226				12,760	15,226
Revenue									3,075	7,943	8,770
Net Revenue									3,075	7,943	8,770
Royalty Interest | Other.
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	42,720				51,398				42,720	51,398
Revenue									9,659	10,883	13,394
Net Revenue									9,659	10,883	$ 13,394
Stream Interest
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	831,274				816,408				831,274	816,408
Stream Interest | Canada
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	823,091				$ 816,408				823,091	816,408
Revenue									94,104	27,209
Cost of sales									33,450	9,158
Net Revenue									60,654	$ 18,051
Stream Interest | Other.
Long Lived Assets and Pre-Tax Income by Geographical Information
Royalty and stream interests, net	$ 8,183								$ 8,183