FAIR VALUE MEASUREMENTS - Fair value on a recurring basis (Details) $ in Millions	Jun. 30, 2023 USD ($) Y $ / shares
Price Volatility Rate \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants	132.0
Discount yield \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants	4.4
Expected Term \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants \| Y	3.7
Exercise Price \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants \| $ / shares	1.068
Recurring basis
Other long-term assets:
Total assets at fair value	$ 11.6
Recurring basis \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Investments measured at net asset value	4.6
Recurring basis \| Hycroft
Other long-term assets:
The company's recorded investment	7.0
Recurring basis \| Quoted prices in active market (Level 1)
Other long-term assets:
Total assets at fair value	7.0
Recurring basis \| Quoted prices in active market (Level 1) \| Hycroft
Other long-term assets:
The company's recorded investment	7.0
Recurring basis \| Significant unobservable inputs (Level 3)
Other long-term assets:
Total assets at fair value	4.6
Recurring basis \| Significant unobservable inputs (Level 3) \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Investments measured at net asset value	$ 4.6

Value of input used to measure alternative investment.

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