FAIR VALUE MEASUREMENTS - Fair value on a recurring basis (Details) - Recurring basis $ in Millions	Jun. 30, 2025 USD ($)
Other long-term assets:
Total assets at fair value	$ 8.6
Corporate Borrowings:
Derivative liability	116.4
Total liabilities at fair value	116.4
Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Investment in warrants	1.0
Hycroft
Other long-term assets:
Investment in marketable equity securities	7.6
Quoted prices in active market (Level 1)
Other long-term assets:
Total assets at fair value	7.6
Quoted prices in active market (Level 1) \| Hycroft
Other long-term assets:
Investment in marketable equity securities	7.6
Significant unobservable inputs (Level 3)
Other long-term assets:
Total assets at fair value	1.0
Corporate Borrowings:
Derivative liability	116.4
Total liabilities at fair value	116.4
Significant unobservable inputs (Level 3) \| Investment in Hycroft Mining Holding Corporation Warrants
Other long-term assets:
Investment in warrants	$ 1.0

Fair value portion of asset recognized for present right to economic benefit.

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