EARNINGS PER SHARE (EPS) (Details) (USD $) In Thousands, except Share data	3 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
EARNINGS PER SHARE ("EPS")
Net income available to Royal Gold common stockholders	$ 22,495	$ 11,831
Weighted-average shares for basic EPS (in shares)	55,183,719	54,986,700
Effect of other dilutive securities (in shares)	307,635	263,328
Weighted-average shares for diluted EPS (in shares)	55,491,354	55,250,028
Basic earnings per share (in dollars per share)	$ 0.41	$ 0.22
Diluted earnings per share (in dollars per share)	$ 0.40	$ 0.21
Exchange basis for conversion of exchangeable shares of RG Exchangeco into shares of Royal Gold common stock	one-for-one basis