COMMITMENTS AND CONTINGENCIES - Prepayment Agreement (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other commitments
Revenue	$ 58,680,000	$ 38,404,000	$ 34,395,000	$ 34,752,000	$ 28,240,000	$ 25,988,000	$ 30,647,000	$ 25,542,000	$ 166,231,000	$ 110,417,000	$ 136,541,000
Remaining net proceeds recorded as deferred revenue					6,155,000					6,155,000
Auramet International LLC
Other commitments
Revenue									136,911,000	50,580,000
Auramet International LLC | Prepayment Agreement | Guarantee Obligation
Other commitments
Net proceeds from sales on a Supplier Advance Basis									127,000,000.0	46,000,000.0
Revenue										40,600,000
Remaining net proceeds recorded as deferred revenue					$ 6,200,000					$ 6,200,000
Auramet International LLC | Prepayment Agreement | Guarantee Obligation | Precious metal
Other commitments
Revenue									$ 132,700,000
Number of ounces of gold					3,500					3,500