EARNINGS PER SHARE ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2021
EARNINGS PER SHARE ("EPS")
Net income attributable to Royal Gold common stockholders	$ 138,339	$ 239,440	$ 238,982	$ 302,532
Weighted-average shares for basic EPS	65,560,468	65,613,002	65,576,995	65,546,400
Effect of other dilutive securities	64,099	126,108	84,753	81,191
Weighted-average shares for diluted EPS	65,624,567	65,739,110	65,661,748	65,627,591
Basic EPS	$ 2.11	$ 3.64	$ 3.64	$ 4.61
Diluted EPS	$ 2.10	$ 3.63	$ 3.63	$ 4.60