SEGMENT INFORMATION - Reconciliation (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2021
SEGMENT INFORMATION
Total segment gross profit	$ 186,741	$ 343,394	$ 323,101	$ 333,002
Costs and expenses
General and administrative expenses	15,163	39,761	34,612	28,387
Exploration costs				563
Depreciation	215	431	493	356
Impairment of royalty interests		0	4,287
Total costs and expenses	15,378	40,192	39,392	29,306
Gain on sale of Peak Gold JV interest				33,906
Operating income	171,363	303,202	283,709	337,602
Fair value changes in equity securities	(1,350)	(147)	(1,503)	6,017
Interest and other income	1,610	9,952	7,832	2,443
Interest and other expense	(2,787)	(30,867)	(17,170)	(6,419)
Income before income taxes	$ 168,836	$ 282,140	$ 272,868	$ 339,643