QUARTERLY RESULTS OF OPERATIONS (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2012
QUARTERLY RESULTS OF OPERATIONS (UNAUDITED)
Revenue	$ 70,142	$ 57,748	$ 52,785	$ 56,487	$ 57,326	$ 74,166	$ 79,870	$ 77,862	$ 237,162	$ 289,224	$ 263,054
Operating income	31,452	28,614	22,916	25,738	29,924	42,932	50,665	47,646	108,720	171,167	156,634
Net income attributable to Royal Gold Stockholders	$ 16,636	$ 20,143	$ 10,667	$ 15,195	$ 10,701	$ 6,464	$ 27,217	$ 24,771	$ 62,641	$ 69,153	$ 92,476
Basic earnings per share (in dollars per share)	$ 0.26	$ 0.31	$ 0.16	$ 0.23	$ 0.16	$ 0.10	$ 0.42	$ 0.42	$ 0.96	$ 1.09	$ 1.61
Diluted earnings per share (in dollars per share)	$ 0.26	$ 0.31	$ 0.16	$ 0.23	$ 0.16	$ 0.10	$ 0.42	$ 0.41	$ 0.96	$ 1.09	$ 1.61