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v3.23.3

Debt - Casthouse and Surety (Details) € in Millions | 1 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Nov. 30, 2021 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2023 EUR (€) | Dec. 31, 2022 USD ($) | Dec. 09, 2022 USD ($) | Sep. 30, 2022 EUR (€)
Casthouse Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt instrument, term | 8 years |  |  |  |  |
Credit facility maximum amount | $ 130,000,000 |  |  |  |  |
Debt instrument, quarterly installment fee | 1.739% |  |  |  |  |
Debt instrument, remaining payment after drawdown of funds | 60.00% |  |  |  |  |
Medium-term notes, outstanding borrowings |  | $ 86,900,000 |  |  |  |
Casthouse Facility | Iceland revolving line of credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Secured debt |  | 86,200,000 |  | $ 49,400,000 |  |
Medium-term Notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Credit facility maximum amount | € |  |  |  |  |  | € 13.6
Medium-term Notes | EURIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Long-term debt due to affiliates |  | $ 4,800,000 | € 4.5 |  |  |
Iceland term facility | Iceland revolving line of credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate, percentage |  | 3.20% | 3.20% |  |  |
Secured debt |  | $ 0 |  | 1,200,000 |  |
Vlissingen facility agreement | Secured Debt | Vlissingen |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Face amount |  |  |  |  | $ 90,000,000 |
Vlissingen facility agreement | Iceland revolving line of credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate, percentage |  | 8.75% | 8.75% |  |  |
Secured debt |  | $ 10,000,000.0 |  | $ 0 |  |
Surety Bond |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Loss contingency accrual |  | $ 6,600,000 |  |  |  |

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