EARNINGS PER SHARE ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
EARNINGS PER SHARE ("EPS")
Net income attributable to Royal Gold common stockholders	$ 106,939	$ 70,453
Weighted-average shares for basic EPS	65,537,714	65,465,611
Effect of other dilutive securities (in shares)	94,975	150,315
Weighted-average shares for diluted EPS	65,632,689	65,615,926
Basic earnings per share (in dollars per share)	$ 1.63	$ 1.07
Diluted earnings per share (in dollars per share)	$ 1.63	$ 1.07