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RELATIONSHIP AND AGREEMENTS WITH SHENGHE - Framework Agreement and Restructured Commercial Arrangements (Details) - USD ($) $ in Thousands				1 Months Ended		12 Months Ended
	Jun. 05, 2020	Jun. 02, 2020	Jun. 20, 2017	Mar. 31, 2022	May 31, 2017	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Principal payments on debt obligations and finance leases						$ 5,834	$ 2,435	$ 20,180
Affiliated Entity | Shenghe
Related Party Transaction [Line Items]
Principal payments on debt obligations and finance leases				$ 2,900
Original Offtake Agreement, Second Additional Advance | Affiliated Entity | Shenghe
Related Party Transaction [Line Items]
Advances	$ 35,500
Initial Prepayment Amount | Affiliated Entity
Related Party Transaction [Line Items]
Advances					$ 50,000
Increase in advances			$ 30,000
Initial Prepayment Amount | Affiliated Entity | Shenghe
Related Party Transaction [Line Items]
Increase in advances	$ 30,000
MPMO | A&R Offtake Agreement | Affiliated Entity | Shenghe Warrant | Shenghe
Related Party Transaction [Line Items]
Number of preferred units convertible from warrant exercise (in shares)		89.88
Percentage of equity on a diluted basis after warrant exercise		7.50%

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Amount of cash outflow for debt, mandatory redeemable security, and principal payment for finance lease obligation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a),(b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

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