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DEBT AND OFF-BALANCE SHEET ARRANGEMENTS - Narrative (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 24 Months Ended |  |
--- | --- | --- | --- | --- | ---
Mar. 31, 2026 USD ($) | Mar. 31, 2026 USD ($) | Dec. 31, 2025 USD ($) tranche instrument | Mar. 06, 2026 USD ($) | Dec. 31, 2024 USD ($)
Debt Instrument [Line Items] |  |  |  |  |
Principal amount | $ 189,752 | $ 189,752 | $ 175,600 |  |
Unamortized debt issuance costs | 3,116 | 3,116 | 2,763 |  |
Surety bonds |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Off-balance sheet liability | 59,800 | 59,800 | $ 57,500 |  |
Promissory notes | XRC Facility |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Number of promissory notes issued | instrument |  |  | 3 |  |
Number of tranches issued | tranche |  |  | 3 |  |
Principal amount | 145,600 | 145,600 | $ 145,600 |  |
Unamortized debt issuance costs | 2,600 | 2,600 | 2,800 |  |
Debt, estimated fair value | 143,700 | 143,700 | 140,700 |  |
Line of credit | Mercuria Credit Facility |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principal amount | 30,000 | 30,000 | 30,000 |  |
Debt, estimated fair value | 30,000 | 30,000 | 30,000 |  |
Credit agreement amount outstanding | 30,000 | 30,000 | 30,000 |  |
Debt issuance costs incurred, recorded in long-term assets |  |  |  |  | $ 3,500
Off-balance sheet liability | 35,500 | 35,500 | 35,500 |  |
Line of credit | Project Granite Facility |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principal amount | 14,152 | 14,152 | $ 0 |  |
Debt, estimated fair value | 14,200 | 14,200 |  |  |
Aggregate commitments | $ 421,400 | $ 421,400 |  |  |
Commitment fee percentage on unutilized portions |  | 30.00% |  |  |
Line of credit | Project Granite Facility | Construction loan |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principal amount |  |  |  | $ 14,200 |
Credit agreement amount outstanding |  |  |  | 13,700 |
SOFR margin rate |  | 3.00% |  |  |
SOFR floor rate | 0.00% | 0.00% |  |  |
Debt issuance costs incurred, offset against debt |  |  |  | $ 500 |
Line of credit | Project Granite Facility | Term loans | SOFR borrowings |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
SOFR margin rate | 3.00% |  |  |  |
SOFR margin rate, annual increase | 0.10% |  |  |  |
Line of credit | Project Granite Facility | Term loans | Base rate borrowings |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
SOFR margin rate, annual increase | 0.10% |  |  |  |
Base rate margin, percentage lower than SOFR margin | 1.00% |  |  |  |

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