EARNINGS PER SHARE ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
EARNINGS PER SHARE ("EPS")
Net income (loss) available to Royal Gold common stockholders	$ 28,062	$ 15,114	$ 57,850	$ (29,933)
Weighted-average shares for basic EPS	65,149,518	65,073,678	65,133,102	65,061,059
Effect of other dilutive securities (in shares)	103,691	48,066	131,035
Weighted-average shares for diluted EPS	65,253,209	65,121,744	65,264,137	65,061,059
Basic earnings (loss) per share (in dollars per share)	$ 0.43	$ 0.23	$ 0.89	$ (0.46)
Diluted earnings (loss) per share (in dollars per share)	0.43	$ 0.23	0.88	$ (0.46)
2019 Conversion Notes, Initial conversion price per share of common stock (in dollars per share)	$ 103.52		$ 103.52