EARNINGS PER SHARE (EPS) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
EARNINGS PER SHARE ("EPS")
Net income available to Royal Gold common stockholders	$ 23,411	$ 18,312	$ 45,906	$ 30,144
Weighted-average shares for basic EPS (in shares)	55,329,463	55,043,160	55,259,009	55,014,930
Effect of other dilutive securities (in shares)	245,351	265,549	274,239	264,263
Weighted-average shares for diluted EPS (in shares)	55,574,814	55,308,709	55,533,248	55,279,193
Basic earnings per share (in dollars per share)	$ 0.42	$ 0.33	$ 0.83	$ 0.55
Diluted earnings per share (in dollars per share)	$ 0.42	$ 0.33	$ 0.82	$ 0.55
Exchange basis for conversion of exchangeable shares of RG Exchangeco into shares of Royal Gold common stock			one-for-one basis