EARNINGS PER SHARE ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
EARNINGS PER SHARE ("EPS")
Net income attributable to Royal Gold common stockholders	$ 71,140	$ 81,677	$ 136,816	$ 135,705
Weighted-average shares for basic EPS	65,569,190	65,550,682	65,567,621	65,550,542
Effect of other dilutive securities	109,130	86,282	94,032	78,742
Weighted-average shares for diluted EPS	65,678,320	65,636,964	65,661,653	65,629,284
Basic EPS	$ 1.08	$ 1.24	$ 2.08	$ 2.07
Diluted EPS	$ 1.08	$ 1.24	$ 2.08	$ 2.07