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Debt - Narrative (Details) $ / shares in Units, € in Millions |  |  |  |  | 12 Months Ended |  |  |  |  |  |
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Oct. 01, 2024 USD ($) | Nov. 02, 2021 USD ($) | Apr. 14, 2021 USD ($) | Apr. 09, 2021 USD ($) $ / shares | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2022 EUR (€) | Sep. 28, 2022 USD ($) | Jun. 14, 2022 USD ($) | Feb. 04, 2022 USD ($) | Nov. 30, 2013 USD ($)
Senior Secured Notes, 7.5% | Senior Notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage |  |  | 7.50% |  | 7.50% |  |  |  |  |  |
Face amount |  |  | $ 250,000,000 |  |  |  |  |  |  |  |
Proceeds from issuance of Senior Notes due 2028 |  |  | $ 245,200,000 |  |  |  |  |  |  |  |
Redemption price, percentage |  |  |  |  | 100.00% |  |  |  |  |  |
Redemption period |  |  |  |  | 12 months |  |  |  |  |  |
Percentage of outstanding amount, offer to purchase |  |  |  |  | 101.00% |  |  |  |  |  |
Senior Secured Notes, 7.5% | Senior Notes | Level 2 |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Fair value of debt instrument |  |  |  |  | $ 253,100,000 |  |  |  |  |  |
Senior Convertible Notes, 2.75% | Senior Notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage |  |  |  | 2.75% | 2.75% |  |  |  |  |  |
Face amount |  |  |  | $ 86,300,000 |  |  |  |  |  |  |
Percentage of principal amount redeemed |  |  |  | 100.00% | 100.00% |  |  |  |  |  |
Proceeds from issuance of Convertible Senior Notes |  |  |  | $ 83,700,000 |  |  |  |  |  |  |
Conversion ratio |  |  |  | 0.0533547 |  |  |  |  |  |  |
Conversion price (in dollars per share) | $ / shares |  |  |  | $ 18.74 |  |  |  |  |  |  |
Debt instrument, convertible, threshold percentage of stock price trigger |  |  |  |  | 130.00% |  |  |  |  |  |
Debt instrument, trading days, term |  |  |  |  | 20 days |  |  |  |  |  |
Debt instrument, consecutive trading days, term |  |  |  |  | 30 days |  |  |  |  |  |
Senior Convertible Notes, 2.75% | Senior Notes | Level 2 |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Fair value of debt instrument |  |  |  |  | $ 102,600,000 |  |  |  |  |  |
Revolving Credit Facility | U.S revolving credit facility |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage |  |  |  |  | 8.00% |  |  |  |  |  |
Credit facility face amount |  |  |  |  |  |  |  |  | $ 250,000,000.0 |  |
Letter of credit sub-facility amount |  |  |  |  | $ 65,600,000 |  |  |  |  |  |
Outstanding borrowings |  |  |  |  | 20,000,000.0 |  |  |  |  |  |
Outstanding letters of credit issued |  |  |  |  | 63,700,000 |  |  |  |  |  |
Credit facility maximum amount |  |  |  |  | $ 250,000,000.0 |  |  |  |  |  |
Revolving Credit Facility | Letter of Credit |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Letter of credit sub-facility amount |  |  |  |  |  |  |  |  | $ 150,000,000.0 |  |
Revolving Credit Facility | Foreign line of credit |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage |  |  |  |  | 7.84% |  |  |  |  |  |
Credit facility face amount |  |  |  |  |  |  |  | $ 100,000,000.0 |  |  | $ 50,000,000
Outstanding borrowings |  |  |  |  | $ 34,000,000.0 |  |  |  |  |  |
Outstanding letters of credit issued |  |  |  |  | 0 |  |  |  |  |  |
Credit facility maximum amount |  |  |  |  | 100,000,000.0 |  |  |  |  | $ 80,000,000.0 |
Casthouse Facility |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Credit facility face amount |  | $ 130,000,000.0 |  |  |  |  |  |  |  |  |
Debt instrument, term |  | 8 years |  |  |  |  |  |  |  |  |
Debt instrument, quarterly installment fee |  | 1.739% |  |  |  |  |  |  |  |  |
Debt instrument, remaining payment after drawdown of funds |  | 60.00% |  |  |  |  |  |  |  |  |
Medium-term notes, outstanding borrowings |  |  |  |  | $ 123,200,000 |  |  |  |  |  |
Debt instrument, arrangement fee, percentage of facility |  | 0.78% |  |  |  |  |  |  |  |  |
Debt instrument, arrangement fee, paid upfront |  | 50.00% |  |  |  |  |  |  |  |  |
Debt instrument, arrangement fee, paid at end of availability |  | 50.00% |  |  |  |  |  |  |  |  |
Line of credit facility, unused capacity, commitment fee percentage |  | 0.38% |  |  |  |  |  |  |  |  |
Casthouse Facility | Foreign line of credit |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage |  |  |  |  | 8.06% |  |  |  |  |  |
Secured debt |  |  |  |  | $ 114,200,000 | $ 98,800,000 |  |  |  |  |
Casthouse Facility | Secured Debt |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  | $ 430,000,000 |  |  |  |  |  |  |  |  |
Medium-term Notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Credit facility face amount | € |  |  |  |  |  |  | € 13.6 |  |  |  |
Iceland Term Facility | Foreign line of credit |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage |  |  |  |  | 3.20% |  |  |  |  |  |
Vlissingen Credit Facility | Foreign line of credit |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate, percentage | 8.75% |  |  |  | 7.99% |  |  |  |  |  |
Credit facility face amount | $ 90,000,000 |  |  |  |  |  |  |  |  |  |
Term extension | 2 years |  |  |  |  |  |  |  |  |  |
Secured debt |  |  |  |  | $ 10,000,000.0 | $ 0 |  |  |  |  |
Debt instrument, basis spread on variable rate | 3.687% |  |  |  |  |  |  |  |  |  |
Vlissingen Credit Facility | Foreign line of credit | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Variable interest rate | 9.00% |  |  |  |  |  |  |  |  |  |
Vlissingen Credit Facility | Foreign line of credit | Minimum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Variable interest rate | 7.00% |  |  |  |  |  |  |  |  |  |
Industrial Revenue Bonds, Variable |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Maximum variable interest rate |  |  |  |  | 12.00% |  |  |  |  |  |
Surety Bond |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Loss contingency accrual |  |  |  |  | $ 6,600,000 |  |  |  |  |  |

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