ACQUISITION (Details) $ / shares in Units, shares in Millions							1 Months Ended	3 Months Ended
	Sep. 29, 2015 USD ($) oz	Jul. 28, 2015 USD ($) item oz $ / shares shares	Jul. 20, 2015 USD ($) payment oz	Jul. 10, 2015 USD ($) $ / oz	Jul. 09, 2015 USD ($) km oz	Dec. 01, 2010 oz	Sep. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)
Acquisition of Royalty Interest in Mineral Properties
Royalty Revenue.								$ 74,056,000	$ 69,026,000
Carrying value							$ 3,506,446,000	3,506,446,000		$ 2,647,976,000
Royalty and stream interests, net							3,012,952,000	3,012,952,000		2,083,608,000
Chile
Acquisition of Royalty Interest in Mineral Properties
Royalty and stream interests, net							837,595,000	837,595,000		$ 653,019,000
BGC | Pueblo Viejo | Initial Royalty
Acquisition of Royalty Interest in Mineral Properties
Gold delivered (in ounces) | oz	990,000
BGC | Pascua Lama | Chile
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired				1.09%
Golden Star
Acquisition of Royalty Interest in Mineral Properties
Gross loans		$ 20,000,000
Term of loan		4 years
Quarterly interest rate based on average gold rate divided by 10,000		62.50%
Denominator used in calculation of quarterly interest rate		$ 10,000
Number of shares of common stock that can be purchased by the warrants | shares		5
Grant date fair value on exercise of warrants		$ 800,000
Term of warrants		4 years
Exercise price of warrants | $ / shares		$ 0.27
Golden Star | Maximum
Acquisition of Royalty Interest in Mineral Properties
Interest rate (as a percent)		11.50%
Golden Star | Other assets
Acquisition of Royalty Interest in Mineral Properties
Gross loans		$ 20,000,000
Barrick Gold | Pascua Lama
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired				0.22%
Royalty interests in Mineral Property, net (as a percent)				5.45%
Cash paid for acquisition of royalty interests				$ 8,000,000
Gold price (in dollars per ounce) | $ / oz				800
Barrick Gold | Pascua Lama | Royalty and stream interests, net
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount								8,000,000
Barrick Gold | Pascua Lama | First Condition
Acquisition of Royalty Interest in Mineral Properties
Remaining consideration payable				$ 2,000,000
Barrick Gold | Pascua Lama | Second Condition
Acquisition of Royalty Interest in Mineral Properties
Remaining consideration payable				$ 1,000,000
RGLD Gold | Carmen de Andacollo | Royalty and stream interests, net
Acquisition of Royalty Interest in Mineral Properties
Carrying value					$ 388,200,000
RGLD Gold | BGC | Pueblo Viejo
Acquisition of Royalty Interest in Mineral Properties
Ownership interest (as a percent)	60.00%
Total purchase amount	$ 610,000,000
Purchase price per ounce of the commodities as percentage of spot price at the time of delivery	60.00%
RGLD Gold | BGC | Pueblo Viejo | Royalty and stream interests, net
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount								610,000,000
RGLD Gold | BGC | Pueblo Viejo | First Condition
Acquisition of Royalty Interest in Mineral Properties
Maximum quantity of silver with specified purchase price (in ounces) | oz	23,100,000
Purchase price per ounce of the commodities as percentage of spot price at the time of delivery	30.00%
Gold delivered (in ounces) | oz	550,000
RGLD Gold | BGC | Pueblo Viejo | Initial Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired	7.50%
Percentage of silver royalty interests acquired	75.00%
Maximum quantity of silver with specified purchase price (in ounces) | oz	50,000,000
RGLD Gold | BGC | Pueblo Viejo | Subsequent Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired	3.75%
Percentage of silver royalty interests acquired	37.50%
RGLD Gold | Golden Star | Ghana Mines
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount		$ 130,000,000
Number of installments | item		4
Purchase price per ounce of the commodities as percentage of spot price at the time of delivery		30.00%
Allocation to production stage steam interest		$ 46,100,000
Allocation to exploration stage steam interest		10,100,000
First installment		30,000,000
Second, third and fourth scheduled payment		15,000,000
Cash paid for acquisition of royalty interests		$ 40,000,000					$ 15,000,000
RGLD Gold | Golden Star | Ghana Mines | Royalty and stream interests, net
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount								55,000,000
RGLD Gold | Golden Star | Ghana Mines | First Condition
Acquisition of Royalty Interest in Mineral Properties
Purchase price per ounce of the commodities as percentage of spot price at the time of delivery		20.00%
Gold delivered (in ounces) | oz		207,500
RGLD Gold | Golden Star | Ghana Mines | Initial Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired		8.50%
Gold delivered (in ounces) | oz		185,000
RGLD Gold | Golden Star | Ghana Mines | Subsequent Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired		5.00%
Gold delivered (in ounces) | oz		22,500
RGLD Gold | Golden Star | Ghana Mines | Subsequent Two Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired		3.00%
RGLD Gold | New Gold Inc | Rainy River
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount			$ 175,000,000
Number of installments | payment			2
Installment payable upon meeting capital spending requirement			$ 75,000,000
Capital spending requirement (as a percent)			60.00%
Cash paid for acquisition of royalty interests			$ 100,000,000
RGLD Gold | New Gold Inc | Rainy River | Royalty and stream interests, net
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount								$ 100,000,000
RGLD Gold | New Gold Inc | Rainy River | Initial Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired			6.50%
Percentage of silver royalty interests acquired			60.00%
Maximum quantity of silver with specified purchase price (in ounces) | oz			3,100,000
Gold delivered (in ounces) | oz			230,000
RGLD Gold | New Gold Inc | Rainy River | Subsequent Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired			3.25%
Purchase price per ounce of the commodities as percentage of spot price at the time of delivery			25.00%
Percentage of silver royalty interests acquired			30.00%
RGLD Gold | CMCA | Carmen de Andacollo
Acquisition of Royalty Interest in Mineral Properties
Percentage of produced payable gold to be purchased until 48,000 ounces have been delivered					100.00%
Maximum quantity of gold with specified purchase price (in ounces) | oz					900,000
Fixed percentage of produced gold payable (as a percent)					89.00%
Purchase price per ounce as a percentage of monthly average gold price for the month preceding the delivery date					15.00%
Cash paid for acquisition of royalty interests					$ 525,000,000
Percentage of produced payable gold to be purchased after 48,000 ounces have been delivered					50.00%
RGLD Gold | CMCA | Carmen de Andacollo | Maximum
Acquisition of Royalty Interest in Mineral Properties
Area of mining to be eligible for concessions | km					1.5
RG Chile | Carmen de Andacollo
Acquisition of Royalty Interest in Mineral Properties
Royalty and stream interests, net					$ 207,500,000
RG Chile | CMCA | Carmen de Andacollo
Acquisition of Royalty Interest in Mineral Properties
Total purchase amount					$ 345,000,000
RG Chile | CMCA | Carmen de Andacollo | Initial Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired						75.00%
Gold delivered (in ounces) | oz						910,000
RG Chile | CMCA | Carmen de Andacollo | Subsequent Royalty
Acquisition of Royalty Interest in Mineral Properties
Percentage of royalty interests acquired						50.00%
Teck | CMCA
Acquisition of Royalty Interest in Mineral Properties
Ownership interest (as a percent)					90.00%