EARNINGS PER SHARE ("EPS") (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
EARNINGS PER SHARE ("EPS")
Net income available to Royal Gold common stockholders	$ 27,217	$ 23,411	$ 51,987	$ 45,906
Weighted-average shares for basic EPS	63,941,686	55,329,463	61,688,776	55,259,009
Effect of other dilutive securities (in shares)	195,551	245,351	216,773	274,239
Weighted-average shares for diluted EPS	64,137,237	55,574,814	61,905,549	55,533,248
Basic earnings per share (in dollars per share)	$ 0.42	$ 0.42	$ 0.84	$ 0.83
Diluted earnings per share (in dollars per share)	$ 0.42	$ 0.42	$ 0.84	$ 0.82
Exchange ratio for conversion of exchangeable shares of RG Exchangeco into shares of Royal Gold common stock			1
2019 Conversion Notes, Initial conversion price per share of common stock (in dollars per share)	$ 105.31		$ 105.31