FAIR VALUE MEASUREMENTS - Fair value on a recurring basis (Details) $ in Millions	Sep. 30, 2022 USD ($) Y $ / shares
Price Volatility Rate \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants	1.149
Discount yield \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants	0.041
Expected Term \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Estimates to value Warrants \| Y	4.5
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	$ 28.4
Recurring basis \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Investments measured at net asset value	10.3
Recurring basis \| NCM
Other long-term assets:
The company's recorded investment	3.9
Recurring basis \| Hycroft
Other long-term assets:
The company's recorded investment	14.2
Recurring basis \| Quoted prices in active market (Level 1)
Other long-term assets:
Total assets at fair value	18.1
Recurring basis \| Quoted prices in active market (Level 1) \| NCM
Other long-term assets:
The company's recorded investment	3.9
Recurring basis \| Quoted prices in active market (Level 1) \| Hycroft
Other long-term assets:
The company's recorded investment	14.2
Recurring basis \| Significant unobservable inputs (Level 3)
Other long-term assets:
Total assets at fair value	10.3
Recurring basis \| Significant unobservable inputs (Level 3) \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Investments measured at net asset value	$ 10.3

Value of input used to measure alternative investment.

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