EARNINGS PER SHARE ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
EARNINGS PER SHARE ("EPS")
Net income attributable to Royal Gold common stockholders	$ 45,792	$ 70,176	$ 182,609	$ 205,879
Weighted-average shares for basic EPS	65,579,834	65,556,608	65,571,737	65,552,586
Effect of other dilutive securities	80,318	71,237	89,460	76,241
Weighted-average shares for diluted EPS	65,660,152	65,627,845	65,661,197	65,628,827
Basic EPS	$ 0.70	$ 1.07	$ 2.78	$ 3.14
Diluted EPS	$ 0.70	$ 1.07	$ 2.78	$ 3.13