NOTES PAYABLE AND DEBT INSTRUMENTS - Revenue Bonds (Details) - Revenue Bonds lb in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Nov. 08, 2023 USD ($) d lb	Mar. 15, 2023 USD ($) lb	Jan. 31, 2022 USD ($)	Mar. 17, 2021 USD ($)	Oct. 07, 2020 USD ($) series purchaser supplier
Debt Instrument [Line Items]
Number of debt offering series | series									3
Debt instrument, discount									$ 5,500,000
Escrow deposit									$ 50,000,000.0
Operating revenue deposit requirement, percent									100.00%
Equity investments								$ 40,000,000	$ 60,000,000
Cash required to maintain							$ 100,000,000
Interest expense	$ 4,900,000	$ 4,800,000	$ 14,600,000	$ 14,500,000
Capitalized interest	0	$ 4,200,000	7,100,000	$ 12,800,000
Fair value of revenue bonds	$ 169,400,000		$ 169,400,000
Number of suppliers | supplier									1
Number of purchasers | purchaser									2,000
Escrow deposit, stated conditions satisfied, amount									$ 25,000,000.0
Ironton Facility
Debt Instrument [Line Items]
Loan agreement, limited waiver terms, deposit in equity with the trustee						$ 87,300,000
Loan agreement, limited waiver terms, financing transaction milestone amount						$ 150,000,000
Loan agreement, limited waiver terms, production targets | lb						107,000
Loan agreement, limited waiver terms, deposit controlled by the trustee						$ 50,000,000
Loan agreement, limited waiver terms, deposit in equity amount to fund remaining construction costs						25,000,000
Loan agreement, limited waiver terms, deposit into capitalized interest accounts						12,300,000
Loan agreement, limited waiver terms, liquidity reserve escrow fund amount						50,000,000
Loan agreement, limited waiver terms, amount released from the trustee for investment						13,200,000
Ironton Facility | Subsequent Event
Debt Instrument [Line Items]
Loan agreement, Second Limited Waiver terms, additional collateral required to deposit					$ 50,000,000
Loan agreement, Second Limited Waiver terms, aggregate trustee deposit					100,000,000
Loan Agreement, Second Limited Waiver terms, amount shall be released upon satisfaction of conditions					$ 50,000,000
Expected investment to complete facility, September Milestone Event of Default, amount (in pounds) | lb					4,450
Expected investment to complete facility, September Milestone Event of Default, amount, period | d					30
Loan agreement, Second Limited Waiver terms, revised milestone amount (in pounds) | lb					8,900
Loan agreement, Second Limited Waiver terms, revised capacity, amount (in pounds) | lb					107,000
Loan agreement, Second Limited Waiver terms, revised capacity, period | d					90
Minimum | Ironton Facility
Debt Instrument [Line Items]
Loan agreement, limited waiver terms, liquidity reserve escrow fund amount						$ 25,000,000