SUPPLEMENTAL BALANCE SHEET INFORMATION - Other Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
PPA income receivable	$ 8,109	$ 51,016
Government grant receivable	23,457	41,980
Other receivables	15,566	4,718
Other receivables	57,638	132,042
United States Department of War
Accounts, Notes, Loans and Financing Receivable [Line Items]
DoW reimbursable costs receivable	2,506	2,328
Apple
Accounts, Notes, Loans and Financing Receivable [Line Items]
Apple prepayment receivable	$ 8,000	$ 32,000

DoW Offtake Agreement, Reimbursable Costs Receivable

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- Definition

Prepayment Receivable

+ References

No definition available.

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- Definition

Price Protection Agreement Income, Receivable

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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- Definition

Carrying amounts due as of the balance sheet date of the sum of amounts receivable other than from customers.

+ References

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- Definition

Amount due from parties in nontrade transactions, classified as other.

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