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Stock-Based Compensation - Narratives (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2021 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-based compensation expense |  | $ 2,311 | $ 16,631 | $ 2,665
Accelerated stock-based compensation expense | $ 14,700 |  | 14,700 |
Share-based Payment Arrangement, Expense, Tax Benefit |  | $ 100 | 1,800 | 500
Plan |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Accelerated stock-based compensation expense |  |  | 13,800 |
Plan | Brookfield | GrafTech International Ltd |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Equity Method Investment, Ownership Percentage | 30.00% | 30.00% |  |
Scenario, Adjustment |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Accelerated stock-based compensation expense |  |  | 900 |
Scenario, Adjustment | Brookfield | GrafTech International Ltd |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Equity Method Investment, Ownership Percentage | 35.00% |  |  |
Selling, General and Administrative Expenses |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-based compensation expense |  | $ 2,100 | $ 14,600 | $ 2,300

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