| \u00a0 | Years | ||||
| Buildings | 25-40 | ||||
| Land improvements | 20 | ||||
| Machinery and equipment | 5-20 | ||||
| Furniture and fixtures | 5-10 |
| \u00a0 | Years | ||||
| Trade names | 5-20 | ||||
| Technology and know-how | 5-14 | ||||
| Customer-related intangibles | 5-15 |
| \u00a0 | Years | ||||
| Buildings | 25-40 | ||||
| Land improvements | 20 | ||||
| Machinery and equipment | 5-20 | ||||
| Furniture and fixtures | 5-10 |
| \u00a0 | Years | ||||
| Buildings | 25-40 | ||||
| Land improvements | 20 | ||||
| Machinery and equipment | 5-20 | ||||
| Furniture and fixtures | 5-10 |
| \u00a0 | Years | ||||
| Trade names | 5-20 | ||||
| Technology and know-how | 5-14 | ||||
| Customer-related intangibles | 5-15 |
| \u00a0 | Years | ||||
| Trade names | 5-20 | ||||
| Technology and know-how | 5-14 | ||||
| Customer-related intangibles | 5-15 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars in thousands) | |||||||||||||||||
| Graphite Electrodes - LTAs | $ | 116,786\u00a0 | $ | 253,262\u00a0 | $ | 870,287\u00a0 | |||||||||||
| Graphite Electrodes - Non-LTAs | 376,858\u00a0 | 338,746\u00a0 | 351,140\u00a0 | ||||||||||||||
| By-products and other | 45,138\u00a0 | 28,492\u00a0 | 59,823\u00a0 | ||||||||||||||
| Total Revenues | $ | 538,782\u00a0 | $ | 620,500\u00a0 | $ | 1,281,250\u00a0 |
| December 31, 2024 | December 31, 2023 | ||||||||||
| (Dollars in thousands) | |||||||||||
| Current deferred revenue | $ | 11,223\u00a0 | $ | 31,583\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars in thousands) | |||||||||||||||||
| Graphite Electrodes - LTAs | $ | 116,786\u00a0 | $ | 253,262\u00a0 | $ | 870,287\u00a0 | |||||||||||
| Graphite Electrodes - Non-LTAs | 376,858\u00a0 | 338,746\u00a0 | 351,140\u00a0 | ||||||||||||||
| By-products and other | 45,138\u00a0 | 28,492\u00a0 | 59,823\u00a0 | ||||||||||||||
| Total Revenues | $ | 538,782\u00a0 | $ | 620,500\u00a0 | $ | 1,281,250\u00a0 |
| December 31, 2024 | December 31, 2023 | ||||||||||
| (Dollars in thousands) | |||||||||||
| Current deferred revenue | $ | 11,223\u00a0 | $ | 31,583\u00a0 |
| 2023 | 2022 | |||||||||||||
| Dividend yield | 0.71% - 0.83% | 0.40% - 0.56% | ||||||||||||
| Expected volatility | 58.16\u00a0 | % | 58.14\u00a0 | % | ||||||||||
| Risk-free interest rate | 3.60% - 4.10% | 1.93% - 2.89% | ||||||||||||
| Expected term in years | 6.0 years | 6.5 years |
| Number of Options | Weighted- Average Exercise Price Per Share | Aggregate Intrinsic Value (thousands) | Weighted Average Remaining Term (Years) | |||||||||||||||||||||||
Outstanding at December\u00a031, 2023 | 2,027,611\u00a0 | $ | 11.27\u00a0 | |||||||||||||||||||||||
| Granted | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||||||||||||||
| Exercised | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||||||||||||||
| Forfeited or expired | (34,939) | 6.94\u00a0 | ||||||||||||||||||||||||
Outstanding at December\u00a031, 2024 | 1,992,672\u00a0 | $ | 11.34\u00a0 | $ | \u2014\u00a0 | 5.5 years | ||||||||||||||||||||
Vested and Expected to vest as of December\u00a031, 2024 | 1,992,672\u00a0 | $ | 11.34\u00a0 | $ | \u2014\u00a0 | 5.5 years | ||||||||||||||||||||
Exercisable at December\u00a031, 2024 | 1,611,366\u00a0 | $ | 12.25\u00a0 | $ | \u2014\u00a0 | 5.0 years |
| Number of Options | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding unvested as of December\u00a031, 2023 | 582,994\u00a0 | $ | 4.04\u00a0 | |||||||||||
| \u00a0\u00a0\u00a0\u00a0Granted | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Vested | (174,225) | 3.87\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Forfeited | (27,463) | 4.01\u00a0 | ||||||||||||
Outstanding unvested as of December\u00a031, 2024 | 381,306\u00a0 | $ | 4.12\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding unvested as of December\u00a031, 2023 | 885,365\u00a0 | $ | 7.18\u00a0 | |||||||||||
| \u00a0\u00a0\u00a0\u00a0Granted | 3,299,462\u00a0 | 1.80\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Cancelled | (322,093) | 3.36\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Vested | (263,661) | 6.92\u00a0 | ||||||||||||
Outstanding unvested as of December\u00a031, 2024 | 3,599,073\u00a0 | $ | 2.61\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding as of December\u00a031, 2023 | 348,015\u00a0 | $ | 7.23\u00a0 | |||||||||||
| Granted | 1,477,084\u00a0 | 1.06\u00a0 | ||||||||||||
| Vested | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||
| Forfeited | (67,268) | 3.88\u00a0 | ||||||||||||
Outstanding as of December\u00a031, 2024 | 1,757,831\u00a0 | $ | 2.17\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding as of December\u00a031, 2023 | 130,923\u00a0 | $ | 4.25\u00a0 | |||||||||||
| Granted | 395,480\u00a0 | 1.72\u00a0 | ||||||||||||
| Vested and delivered | (136,965) | 2.15\u00a0 | ||||||||||||
Outstanding vested and deferred as of December\u00a031, 2024 | 389,438\u00a0 | $ | 2.42\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding as of December\u00a031, 2023 | 377,540\u00a0 | $ | 6.52\u00a0 | |||||||||||
| Granted | 262,906\u00a0 | 1.30\u00a0 | ||||||||||||
| Distributed | (109,334) | 6.44\u00a0 | ||||||||||||
Outstanding vested and deferred as of December\u00a031, 2024 | 531,112\u00a0 | $ | 3.95\u00a0 |
| 2023 | 2022 | |||||||||||||
| Dividend yield | 0.71% - 0.83% | 0.40% - 0.56% | ||||||||||||
| Expected volatility | 58.16\u00a0 | % | 58.14\u00a0 | % | ||||||||||
| Risk-free interest rate | 3.60% - 4.10% | 1.93% - 2.89% | ||||||||||||
| Expected term in years | 6.0 years | 6.5 years |
| Number of Options | Weighted- Average Exercise Price Per Share | Aggregate Intrinsic Value (thousands) | Weighted Average Remaining Term (Years) | |||||||||||||||||||||||
Outstanding at December\u00a031, 2023 | 2,027,611\u00a0 | $ | 11.27\u00a0 | |||||||||||||||||||||||
| Granted | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||||||||||||||
| Exercised | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||||||||||||||
| Forfeited or expired | (34,939) | 6.94\u00a0 | ||||||||||||||||||||||||
Outstanding at December\u00a031, 2024 | 1,992,672\u00a0 | $ | 11.34\u00a0 | $ | \u2014\u00a0 | 5.5 years | ||||||||||||||||||||
Vested and Expected to vest as of December\u00a031, 2024 | 1,992,672\u00a0 | $ | 11.34\u00a0 | $ | \u2014\u00a0 | 5.5 years | ||||||||||||||||||||
Exercisable at December\u00a031, 2024 | 1,611,366\u00a0 | $ | 12.25\u00a0 | $ | \u2014\u00a0 | 5.0 years |
| Number of Options | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding unvested as of December\u00a031, 2023 | 582,994\u00a0 | $ | 4.04\u00a0 | |||||||||||
| \u00a0\u00a0\u00a0\u00a0Granted | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Vested | (174,225) | 3.87\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Forfeited | (27,463) | 4.01\u00a0 | ||||||||||||
Outstanding unvested as of December\u00a031, 2024 | 381,306\u00a0 | $ | 4.12\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding unvested as of December\u00a031, 2023 | 885,365\u00a0 | $ | 7.18\u00a0 | |||||||||||
| \u00a0\u00a0\u00a0\u00a0Granted | 3,299,462\u00a0 | 1.80\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Cancelled | (322,093) | 3.36\u00a0 | ||||||||||||
| \u00a0\u00a0\u00a0\u00a0Vested | (263,661) | 6.92\u00a0 | ||||||||||||
Outstanding unvested as of December\u00a031, 2024 | 3,599,073\u00a0 | $ | 2.61\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding as of December\u00a031, 2023 | 348,015\u00a0 | $ | 7.23\u00a0 | |||||||||||
| Granted | 1,477,084\u00a0 | 1.06\u00a0 | ||||||||||||
| Vested | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||
| Forfeited | (67,268) | 3.88\u00a0 | ||||||||||||
Outstanding as of December\u00a031, 2024 | 1,757,831\u00a0 | $ | 2.17\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding as of December\u00a031, 2023 | 130,923\u00a0 | $ | 4.25\u00a0 | |||||||||||
| Granted | 395,480\u00a0 | 1.72\u00a0 | ||||||||||||
| Vested and delivered | (136,965) | 2.15\u00a0 | ||||||||||||
Outstanding vested and deferred as of December\u00a031, 2024 | 389,438\u00a0 | $ | 2.42\u00a0 |
| Number of Shares | Weighted- Average Grant Date Fair Value | |||||||||||||
Outstanding as of December\u00a031, 2023 | 377,540\u00a0 | $ | 6.52\u00a0 | |||||||||||
| Granted | 262,906\u00a0 | 1.30\u00a0 | ||||||||||||
| Distributed | (109,334) | 6.44\u00a0 | ||||||||||||
Outstanding vested and deferred as of December\u00a031, 2024 | 531,112\u00a0 | $ | 3.95\u00a0 |
| Year Ended December 31, | |||||||||||
| 2024 | 2023 | 2022 | |||||||||
| (Dollars in thousands) | |||||||||||
| Net sales | $ | 538,782\u00a0 | $ | 620,500\u00a0 | $ | 1,281,250\u00a0 | |||||
Cash cost of goods sold(1) | 442,699\u00a0 | 507,233\u00a0 | 636,082\u00a0 | ||||||||
| Other segment expenses | 91,058\u00a0 | 64,624\u00a0 | 90,291\u00a0 | ||||||||
| Lower of cost or market inventory valuation adjustment | 24,878\u00a0 | 12,431\u00a0 | \u2014\u00a0 | ||||||||
| Research and development | 5,706\u00a0 | 5,520\u00a0 | 3,641\u00a0 | ||||||||
| Selling and administrative expenses | 46,510\u00a0 | 74,012\u00a0 | 76,977\u00a0 | ||||||||
| Rationalization expenses | 3,156\u00a0 | \u2014\u00a0 | \u2014\u00a0 | ||||||||
| Goodwill impairment charges | \u2014\u00a0 | 171,117\u00a0 | \u2014\u00a0 | ||||||||
| Other (income) expense, net | (1,569) | 4,679\u00a0 | (10,147) | ||||||||
| Interest expense | 85,313\u00a0 | 58,087\u00a0 | 36,568\u00a0 | ||||||||
| Interest income | (5,701) | (3,439) | (4,480) | ||||||||
| Income tax (benefit) expense | (22,103) | (18,514) | 69,356\u00a0 | ||||||||
| Net (loss) income | $ | (131,165) | $ | (255,250) | $ | 382,962\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Net sales: | |||||||||||||||||
| United States | $ | 171,192\u00a0 | $ | 206,263\u00a0 | $ | 340,793\u00a0 | |||||||||||
| Americas (excluding the United States) | 95,513\u00a0 | 100,364\u00a0 | 256,253\u00a0 | ||||||||||||||
| Asia Pacific | 57,581\u00a0 | 66,214\u00a0 | 116,849\u00a0 | ||||||||||||||
| Europe, Middle East, Africa | 214,496\u00a0 | 247,659\u00a0 | 567,355\u00a0 | ||||||||||||||
| Total | $ | 538,782\u00a0 | $ | 620,500\u00a0 | $ | 1,281,250\u00a0 |
| \u00a0 | December\u00a031, | ||||||||||
| 2024 | 2023 | ||||||||||
| (Dollars in thousands) | |||||||||||
| Long-lived assets (a): | |||||||||||
| United States | $ | 182,087\u00a0 | $ | 196,847\u00a0 | |||||||
| Mexico | 109,020\u00a0 | 117,414\u00a0 | |||||||||
| Brazil | 3,451\u00a0 | 4,424\u00a0 | |||||||||
| France | 84,059\u00a0 | 93,660\u00a0 | |||||||||
| Spain | 103,734\u00a0 | 109,127\u00a0 | |||||||||
| Other countries | 348\u00a0 | 642\u00a0 | |||||||||
| Total | $ | 482,699\u00a0 | $ | 522,114\u00a0 |
| Year Ended December 31, | |||||||||||
| 2024 | 2023 | 2022 | |||||||||
| (Dollars in thousands) | |||||||||||
| Net sales | $ | 538,782\u00a0 | $ | 620,500\u00a0 | $ | 1,281,250\u00a0 | |||||
Cash cost of goods sold(1) | 442,699\u00a0 | 507,233\u00a0 | 636,082\u00a0 | ||||||||
| Other segment expenses | 91,058\u00a0 | 64,624\u00a0 | 90,291\u00a0 | ||||||||
| Lower of cost or market inventory valuation adjustment | 24,878\u00a0 | 12,431\u00a0 | \u2014\u00a0 | ||||||||
| Research and development | 5,706\u00a0 | 5,520\u00a0 | 3,641\u00a0 | ||||||||
| Selling and administrative expenses | 46,510\u00a0 | 74,012\u00a0 | 76,977\u00a0 | ||||||||
| Rationalization expenses | 3,156\u00a0 | \u2014\u00a0 | \u2014\u00a0 | ||||||||
| Goodwill impairment charges | \u2014\u00a0 | 171,117\u00a0 | \u2014\u00a0 | ||||||||
| Other (income) expense, net | (1,569) | 4,679\u00a0 | (10,147) | ||||||||
| Interest expense | 85,313\u00a0 | 58,087\u00a0 | 36,568\u00a0 | ||||||||
| Interest income | (5,701) | (3,439) | (4,480) | ||||||||
| Income tax (benefit) expense | (22,103) | (18,514) | 69,356\u00a0 | ||||||||
| Net (loss) income | $ | (131,165) | $ | (255,250) | $ | 382,962\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Net sales: | |||||||||||||||||
| United States | $ | 171,192\u00a0 | $ | 206,263\u00a0 | $ | 340,793\u00a0 | |||||||||||
| Americas (excluding the United States) | 95,513\u00a0 | 100,364\u00a0 | 256,253\u00a0 | ||||||||||||||
| Asia Pacific | 57,581\u00a0 | 66,214\u00a0 | 116,849\u00a0 | ||||||||||||||
| Europe, Middle East, Africa | 214,496\u00a0 | 247,659\u00a0 | 567,355\u00a0 | ||||||||||||||
| Total | $ | 538,782\u00a0 | $ | 620,500\u00a0 | $ | 1,281,250\u00a0 |
| \u00a0 | December\u00a031, | ||||||||||
| 2024 | 2023 | ||||||||||
| (Dollars in thousands) | |||||||||||
| Long-lived assets (a): | |||||||||||
| United States | $ | 182,087\u00a0 | $ | 196,847\u00a0 | |||||||
| Mexico | 109,020\u00a0 | 117,414\u00a0 | |||||||||
| Brazil | 3,451\u00a0 | 4,424\u00a0 | |||||||||
| France | 84,059\u00a0 | 93,660\u00a0 | |||||||||
| Spain | 103,734\u00a0 | 109,127\u00a0 | |||||||||
| Other countries | 348\u00a0 | 642\u00a0 | |||||||||
| Total | $ | 482,699\u00a0 | $ | 522,114\u00a0 |
December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||
| Initial First Lien Term Loans due 2029 | 175,000\u00a0 | \u2014\u00a0 | |||||||||
| Existing 4.625% Senior Notes due 2028 | 1,755\u00a0 | 500,000\u00a0 | |||||||||
| New 4.625% Second Lien Notes due 2029 | 498,245\u00a0 | \u2014\u00a0 | |||||||||
| Existing 9.875% Senior Notes due 2028 | 3,833\u00a0 | 450,000\u00a0 | |||||||||
| New 9.875% Second Lien Notes due 2029 | 446,167\u00a0 | \u2014\u00a0 | |||||||||
| Other debt | \u2014\u00a0 | 139\u00a0 | |||||||||
| Unamortized debt discount and issuance costs | (38,085) | (24,494) | |||||||||
| Total debt | 1,086,915\u00a0 | 925,645\u00a0 | |||||||||
| Less: Long-term debt, current portion | \u2014\u00a0 | (134) | |||||||||
| Long-term debt | $ | 1,086,915\u00a0 | $ | 925,511\u00a0 |
| \u00a0 | (Dollars in thousands) | ||||
| 2025 | $ | \u2014\u00a0 | |||
| 2026 | \u2014\u00a0 | ||||
| 2027 | \u2014\u00a0 | ||||
| 2028 | 5,588\u00a0 | ||||
| 2029 | 1,119,412\u00a0 | ||||
| 2030 and thereafter | \u2014\u00a0 | ||||
| Total | $ | 1,125,000\u00a0 |
December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||
| Initial First Lien Term Loans due 2029 | 175,000\u00a0 | \u2014\u00a0 | |||||||||
| Existing 4.625% Senior Notes due 2028 | 1,755\u00a0 | 500,000\u00a0 | |||||||||
| New 4.625% Second Lien Notes due 2029 | 498,245\u00a0 | \u2014\u00a0 | |||||||||
| Existing 9.875% Senior Notes due 2028 | 3,833\u00a0 | 450,000\u00a0 | |||||||||
| New 9.875% Second Lien Notes due 2029 | 446,167\u00a0 | \u2014\u00a0 | |||||||||
| Other debt | \u2014\u00a0 | 139\u00a0 | |||||||||
| Unamortized debt discount and issuance costs | (38,085) | (24,494) | |||||||||
| Total debt | 1,086,915\u00a0 | 925,645\u00a0 | |||||||||
| Less: Long-term debt, current portion | \u2014\u00a0 | (134) | |||||||||
| Long-term debt | $ | 1,086,915\u00a0 | $ | 925,511\u00a0 |
| \u00a0 | (Dollars in thousands) | ||||
| 2025 | $ | \u2014\u00a0 | |||
| 2026 | \u2014\u00a0 | ||||
| 2027 | \u2014\u00a0 | ||||
| 2028 | 5,588\u00a0 | ||||
| 2029 | 1,119,412\u00a0 | ||||
| 2030 and thereafter | \u2014\u00a0 | ||||
| Total | $ | 1,125,000\u00a0 |
| \u00a0 | December\u00a031, 2024 | December\u00a031, 2023 | |||||||||||||||||||||||||||||||||
| Gross Carrying Amount | Accumulated Amortization | Net Carrying Amount | Gross Carrying Amount | Accumulated Amortization | Net Carrying Amount | ||||||||||||||||||||||||||||||
| (Dollars in thousands) | |||||||||||||||||||||||||||||||||||
| Trade names | $ | 22,500\u00a0 | $ | (18,226) | $ | 4,274\u00a0 | $ | 22,500\u00a0 | $ | (17,379) | $ | 5,121\u00a0 | |||||||||||||||||||||||
| Technology\u00a0and know-how | 55,300\u00a0 | (48,613) | 6,687\u00a0 | 55,300\u00a0 | (45,746) | 9,554\u00a0 | |||||||||||||||||||||||||||||
| Customer-related\u00a0intangibles | 64,500\u00a0 | (41,063) | 23,437\u00a0 | 64,500\u00a0 | (36,802) | 27,698\u00a0 | |||||||||||||||||||||||||||||
| Total finite-lived intangible assets | $ | 142,300\u00a0 | $ | (107,902) | $ | 34,398\u00a0 | $ | 142,300\u00a0 | $ | (99,927) | $ | 42,373\u00a0 |
| \u00a0 | December\u00a031, 2024 | December\u00a031, 2023 | |||||||||||||||||||||||||||||||||
| Gross Carrying Amount | Accumulated Amortization | Net Carrying Amount | Gross Carrying Amount | Accumulated Amortization | Net Carrying Amount | ||||||||||||||||||||||||||||||
| (Dollars in thousands) | |||||||||||||||||||||||||||||||||||
| Trade names | $ | 22,500\u00a0 | $ | (18,226) | $ | 4,274\u00a0 | $ | 22,500\u00a0 | $ | (17,379) | $ | 5,121\u00a0 | |||||||||||||||||||||||
| Technology\u00a0and know-how | 55,300\u00a0 | (48,613) | 6,687\u00a0 | 55,300\u00a0 | (45,746) | 9,554\u00a0 | |||||||||||||||||||||||||||||
| Customer-related\u00a0intangibles | 64,500\u00a0 | (41,063) | 23,437\u00a0 | 64,500\u00a0 | (36,802) | 27,698\u00a0 | |||||||||||||||||||||||||||||
| Total finite-lived intangible assets | $ | 142,300\u00a0 | $ | (107,902) | $ | 34,398\u00a0 | $ | 142,300\u00a0 | $ | (99,927) | $ | 42,373\u00a0 |
| \u00a0 | Year Ended December 31, | ||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Interest incurred on debt | $ | 68,971\u00a0 | $ | 56,219\u00a0 | $ | 43,609\u00a0 | |||||||||||
| Accretion of original issue discount | 2,163\u00a0 | 2,524\u00a0 | 1,200\u00a0 | ||||||||||||||
| Amortization of debt issuance costs | 3,193\u00a0 | 4,631\u00a0 | 3,475\u00a0 | ||||||||||||||
| Debt modification costs | 18,370\u00a0 | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||||
| Amortization of interest rate swap deferred gains | (7,384) | (5,480) | \u2014\u00a0 | ||||||||||||||
| Unrealized loss (gain) on termination of de-designated interest rate swap | \u2014\u00a0 | 7,111\u00a0 | (7,111) | ||||||||||||||
| Realized gain on termination of de-designated interest rate swap | \u2014\u00a0 | (6,918) | (4,605) | ||||||||||||||
| Total interest expense | $ | 85,313\u00a0 | $ | 58,087\u00a0 | $ | 36,568\u00a0 |
| \u00a0 | Year Ended December 31, | ||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Interest incurred on debt | $ | 68,971\u00a0 | $ | 56,219\u00a0 | $ | 43,609\u00a0 | |||||||||||
| Accretion of original issue discount | 2,163\u00a0 | 2,524\u00a0 | 1,200\u00a0 | ||||||||||||||
| Amortization of debt issuance costs | 3,193\u00a0 | 4,631\u00a0 | 3,475\u00a0 | ||||||||||||||
| Debt modification costs | 18,370\u00a0 | \u2014\u00a0 | \u2014\u00a0 | ||||||||||||||
| Amortization of interest rate swap deferred gains | (7,384) | (5,480) | \u2014\u00a0 | ||||||||||||||
| Unrealized loss (gain) on termination of de-designated interest rate swap | \u2014\u00a0 | 7,111\u00a0 | (7,111) | ||||||||||||||
| Realized gain on termination of de-designated interest rate swap | \u2014\u00a0 | (6,918) | (4,605) | ||||||||||||||
| Total interest expense | $ | 85,313\u00a0 | $ | 58,087\u00a0 | $ | 36,568\u00a0 |
| December 31, 2024 | Total | Level 1 | Level 2 | Level 3 | |||||||||||||||||||
| Assets: | (Dollars in thousands) | ||||||||||||||||||||||
| Foreign currency derivatives | $ | 296\u00a0 | $ | \u2014\u00a0 | $ | 296\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total assets at fair value | $ | 296\u00a0 | $ | \u2014\u00a0 | $ | 296\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Liabilities: | |||||||||||||||||||||||
| Foreign currency derivatives | $ | 248\u00a0 | $ | \u2014\u00a0 | $ | 248\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total liabilities at fair value | $ | 248\u00a0 | $ | \u2014\u00a0 | $ | 248\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| December 31, 2023 | Total | Level 1 | Level 2 | Level 3 | |||||||||||||||||||
| Assets: | (Dollars in thousands) | ||||||||||||||||||||||
| Foreign currency derivatives | $ | 630\u00a0 | $ | \u2014\u00a0 | $ | 630\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total assets at fair value | $ | 630\u00a0 | $ | \u2014\u00a0 | $ | 630\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Liabilities: | |||||||||||||||||||||||
| Foreign currency derivatives | $ | 519\u00a0 | $ | \u2014\u00a0 | $ | 519\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total liabilities at fair value | $ | 519\u00a0 | $ | \u2014\u00a0 | $ | 519\u00a0 | $ | \u2014\u00a0 |
| December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | Notional Amount | Notional Amount | |||||||||
| (Dollars in thousands) | |||||||||||
| Derivative instruments designated as hedges: | |||||||||||
| Foreign currency derivatives | $ | \u2014\u00a0 | $ | 10,684\u00a0 | |||||||
| Derivative instruments not designated as hedges: | |||||||||||
| Foreign currency derivatives | $ | 11,918\u00a0 | $ | 41,863\u00a0 |
| December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | \u00a0\u00a0\u00a0Fair\u00a0Value | \u00a0\u00a0\u00a0Fair\u00a0Value | |||||||||
| (Dollars in thousands) | |||||||||||
| Prepaid and other current assets | |||||||||||
| Foreign currency derivatives | $ | \u2014\u00a0 | $ | 386\u00a0 | |||||||
| Total | $ | \u2014\u00a0 | $ | 386\u00a0 | |||||||
| Total asset | $ | \u2014\u00a0 | $ | 386\u00a0 |
| \u00a0 | \u00a0 | Amount\u00a0of\u00a0Loss/(Gain) Recognized | ||||||||||||||||||||||||
| Location of Realized Loss/(Gain) Recognized in the Consolidated Statement of Operations | 2024 | 2023 | 2022 | |||||||||||||||||||||||
| Derivatives designated as cash flow hedges: | (Dollars in thousands) | |||||||||||||||||||||||||
| Foreign currency derivatives | Cost of goods sold | $ | 121\u00a0 | $ | 5,541\u00a0 | $ | 1,975\u00a0 | |||||||||||||||||||
| Commodity derivative contracts | Cost of goods sold | (2,462) | (15,089) | (11,452) | ||||||||||||||||||||||
| Interest rate swaps | Interest expense | (7,384) | (10,617) | (2,423) |
| \u00a0 | \u00a0 | Amount\u00a0of\u00a0Loss/(Gain) Recognized | ||||||||||||||||||||||||
| Location of Realized Loss/(Gain) Recognized in the Consolidated Statement of Operations | 2024 | 2023 | 2022 | |||||||||||||||||||||||
| Derivatives not designated as hedges: | (Dollars in thousands) | |||||||||||||||||||||||||
| Foreign currency derivatives | Cost of goods sold, other expense (income), net | $ | 492\u00a0 | $ | (314) | $ | (938) | |||||||||||||||||||
| Interest rate swaps | Interest expense | \u2014\u00a0 | (2,957) | (11,716) |
| December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | \u00a0\u00a0\u00a0Fair\u00a0Value | \u00a0\u00a0\u00a0Fair\u00a0Value | |||||||||
| (Dollars in thousands) | |||||||||||
| Prepaid and other current assets | |||||||||||
| Foreign currency derivatives | $ | 296\u00a0 | $ | 244\u00a0 | |||||||
| Other accrued liabilities | |||||||||||
| Foreign currency derivatives | (248) | (519) | |||||||||
| Net asset (liability) | $ | 48\u00a0 | $ | (275) |
| December 31, 2024 | Total | Level 1 | Level 2 | Level 3 | |||||||||||||||||||
| Assets: | (Dollars in thousands) | ||||||||||||||||||||||
| Foreign currency derivatives | $ | 296\u00a0 | $ | \u2014\u00a0 | $ | 296\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total assets at fair value | $ | 296\u00a0 | $ | \u2014\u00a0 | $ | 296\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Liabilities: | |||||||||||||||||||||||
| Foreign currency derivatives | $ | 248\u00a0 | $ | \u2014\u00a0 | $ | 248\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total liabilities at fair value | $ | 248\u00a0 | $ | \u2014\u00a0 | $ | 248\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| December 31, 2023 | Total | Level 1 | Level 2 | Level 3 | |||||||||||||||||||
| Assets: | (Dollars in thousands) | ||||||||||||||||||||||
| Foreign currency derivatives | $ | 630\u00a0 | $ | \u2014\u00a0 | $ | 630\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total assets at fair value | $ | 630\u00a0 | $ | \u2014\u00a0 | $ | 630\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Liabilities: | |||||||||||||||||||||||
| Foreign currency derivatives | $ | 519\u00a0 | $ | \u2014\u00a0 | $ | 519\u00a0 | $ | \u2014\u00a0 | |||||||||||||||
| Total liabilities at fair value | $ | 519\u00a0 | $ | \u2014\u00a0 | $ | 519\u00a0 | $ | \u2014\u00a0 |
| December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | Notional Amount | Notional Amount | |||||||||
| (Dollars in thousands) | |||||||||||
| Derivative instruments designated as hedges: | |||||||||||
| Foreign currency derivatives | $ | \u2014\u00a0 | $ | 10,684\u00a0 | |||||||
| Derivative instruments not designated as hedges: | |||||||||||
| Foreign currency derivatives | $ | 11,918\u00a0 | $ | 41,863\u00a0 |
| December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | \u00a0\u00a0\u00a0Fair\u00a0Value | \u00a0\u00a0\u00a0Fair\u00a0Value | |||||||||
| (Dollars in thousands) | |||||||||||
| Prepaid and other current assets | |||||||||||
| Foreign currency derivatives | $ | \u2014\u00a0 | $ | 386\u00a0 | |||||||
| Total | $ | \u2014\u00a0 | $ | 386\u00a0 | |||||||
| Total asset | $ | \u2014\u00a0 | $ | 386\u00a0 |
| \u00a0 | \u00a0 | Amount\u00a0of\u00a0Loss/(Gain) Recognized | ||||||||||||||||||||||||
| Location of Realized Loss/(Gain) Recognized in the Consolidated Statement of Operations | 2024 | 2023 | 2022 | |||||||||||||||||||||||
| Derivatives designated as cash flow hedges: | (Dollars in thousands) | |||||||||||||||||||||||||
| Foreign currency derivatives | Cost of goods sold | $ | 121\u00a0 | $ | 5,541\u00a0 | $ | 1,975\u00a0 | |||||||||||||||||||
| Commodity derivative contracts | Cost of goods sold | (2,462) | (15,089) | (11,452) | ||||||||||||||||||||||
| Interest rate swaps | Interest expense | (7,384) | (10,617) | (2,423) |
| \u00a0 | \u00a0 | Amount\u00a0of\u00a0Loss/(Gain) Recognized | ||||||||||||||||||||||||
| Location of Realized Loss/(Gain) Recognized in the Consolidated Statement of Operations | 2024 | 2023 | 2022 | |||||||||||||||||||||||
| Derivatives not designated as hedges: | (Dollars in thousands) | |||||||||||||||||||||||||
| Foreign currency derivatives | Cost of goods sold, other expense (income), net | $ | 492\u00a0 | $ | (314) | $ | (938) | |||||||||||||||||||
| Interest rate swaps | Interest expense | \u2014\u00a0 | (2,957) | (11,716) |
| December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | \u00a0\u00a0\u00a0Fair\u00a0Value | \u00a0\u00a0\u00a0Fair\u00a0Value | |||||||||
| (Dollars in thousands) | |||||||||||
| Prepaid and other current assets | |||||||||||
| Foreign currency derivatives | $ | 296\u00a0 | $ | 244\u00a0 | |||||||
| Other accrued liabilities | |||||||||||
| Foreign currency derivatives | (248) | (519) | |||||||||
| Net asset (liability) | $ | 48\u00a0 | $ | (275) |
December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||
| Inventories: | |||||||||||
| \u00a0\u00a0\u00a0Raw materials and supplies | $ | 78,386\u00a0 | $ | 109,084\u00a0 | |||||||
| \u00a0\u00a0\u00a0Work in process | 122,590\u00a0 | 186,473\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Finished goods | 30,265\u00a0 | 34,589\u00a0 | |||||||||
| $ | 231,241\u00a0 | $ | 330,146\u00a0 | ||||||||
| Prepaid expenses and other current assets: | |||||||||||
| \u00a0\u00a0\u00a0Prepaid expenses | $ | 11,258\u00a0 | $ | 11,176\u00a0 | |||||||
| \u00a0\u00a0\u00a0Value-added tax and other indirect taxes receivable | 21,922\u00a0 | 28,629\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Spare parts inventory | 14,189\u00a0 | 15,242\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Other current assets | 8,363\u00a0 | 11,335\u00a0 | |||||||||
| $ | 55,732\u00a0 | $ | 66,382\u00a0 | ||||||||
| Property, plant and equipment: | |||||||||||
| \u00a0\u00a0\u00a0Land and improvements | $ | 49,212\u00a0 | $ | 49,962\u00a0 | |||||||
| \u00a0\u00a0\u00a0Buildings | 85,871\u00a0 | 87,820\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Machinery and equipment and other | 731,783\u00a0 | 717,002\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Construction in progress | 43,381\u00a0 | 65,660\u00a0 | |||||||||
| $ | 910,247\u00a0 | $ | 920,444\u00a0 | ||||||||
| Other accrued liabilities: | |||||||||||
| \u00a0\u00a0\u00a0Payrolls (including incentive programs) | $ | 9,979\u00a0 | $ | 22,369\u00a0 | |||||||
| \u00a0\u00a0\u00a0Employee benefits | 6,074\u00a0 | 7,018\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Deferred revenue | 11,223\u00a0 | 31,583\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Other | 28,156\u00a0 | 30,732\u00a0 | |||||||||
| $ | 55,432\u00a0 | $ | 91,702\u00a0 | ||||||||
| Other long-term obligations: | |||||||||||
| Post-employment benefits | $ | 10,969\u00a0 | $ | 12,613\u00a0 | |||||||
| Pension and related benefits | 21,919\u00a0 | 26,068\u00a0 | |||||||||
| Other | 15,671\u00a0 | 16,964\u00a0 | |||||||||
| $ | 48,559\u00a0 | $ | 55,645\u00a0 |
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Balance at beginning of year | $ | 7,708\u00a0 | $ | 8,019\u00a0 | $ | 6,835\u00a0 | |||||||||||
| (Credit) charge to income | (660) | (439) | 1,585\u00a0 | ||||||||||||||
| Deductions | 66\u00a0 | 128\u00a0 | (401) | ||||||||||||||
| Balance at end of year | $ | 7,114\u00a0 | $ | 7,708\u00a0 | $ | 8,019\u00a0 |
| (Dollars in thousands) | |||||
| Confirmed obligations outstanding as of December 31, 2022 | $ | \u2014\u00a0 | |||
| Invoices confirmed during the year | 24,368\u00a0 | ||||
| Confirmed invoices paid during the year | (19,732) | ||||
| Confirmed obligations outstanding as of December 31, 2023 | $ | 4,636\u00a0 | |||
| Invoices confirmed during the year | 17,821\u00a0 | ||||
| Confirmed invoices paid during the year | (16,871) | ||||
| Confirmed obligations outstanding as of December 31, 2024 | $ | 5,586\u00a0 |
December 31, 2024 | December 31, 2023 | ||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||
| Inventories: | |||||||||||
| \u00a0\u00a0\u00a0Raw materials and supplies | $ | 78,386\u00a0 | $ | 109,084\u00a0 | |||||||
| \u00a0\u00a0\u00a0Work in process | 122,590\u00a0 | 186,473\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Finished goods | 30,265\u00a0 | 34,589\u00a0 | |||||||||
| $ | 231,241\u00a0 | $ | 330,146\u00a0 | ||||||||
| Prepaid expenses and other current assets: | |||||||||||
| \u00a0\u00a0\u00a0Prepaid expenses | $ | 11,258\u00a0 | $ | 11,176\u00a0 | |||||||
| \u00a0\u00a0\u00a0Value-added tax and other indirect taxes receivable | 21,922\u00a0 | 28,629\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Spare parts inventory | 14,189\u00a0 | 15,242\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Other current assets | 8,363\u00a0 | 11,335\u00a0 | |||||||||
| $ | 55,732\u00a0 | $ | 66,382\u00a0 | ||||||||
| Property, plant and equipment: | |||||||||||
| \u00a0\u00a0\u00a0Land and improvements | $ | 49,212\u00a0 | $ | 49,962\u00a0 | |||||||
| \u00a0\u00a0\u00a0Buildings | 85,871\u00a0 | 87,820\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Machinery and equipment and other | 731,783\u00a0 | 717,002\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Construction in progress | 43,381\u00a0 | 65,660\u00a0 | |||||||||
| $ | 910,247\u00a0 | $ | 920,444\u00a0 | ||||||||
| Other accrued liabilities: | |||||||||||
| \u00a0\u00a0\u00a0Payrolls (including incentive programs) | $ | 9,979\u00a0 | $ | 22,369\u00a0 | |||||||
| \u00a0\u00a0\u00a0Employee benefits | 6,074\u00a0 | 7,018\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Deferred revenue | 11,223\u00a0 | 31,583\u00a0 | |||||||||
| \u00a0\u00a0\u00a0Other | 28,156\u00a0 | 30,732\u00a0 | |||||||||
| $ | 55,432\u00a0 | $ | 91,702\u00a0 | ||||||||
| Other long-term obligations: | |||||||||||
| Post-employment benefits | $ | 10,969\u00a0 | $ | 12,613\u00a0 | |||||||
| Pension and related benefits | 21,919\u00a0 | 26,068\u00a0 | |||||||||
| Other | 15,671\u00a0 | 16,964\u00a0 | |||||||||
| $ | 48,559\u00a0 | $ | 55,645\u00a0 |
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Balance at beginning of year | $ | 7,708\u00a0 | $ | 8,019\u00a0 | $ | 6,835\u00a0 | |||||||||||
| (Credit) charge to income | (660) | (439) | 1,585\u00a0 | ||||||||||||||
| Deductions | 66\u00a0 | 128\u00a0 | (401) | ||||||||||||||
| Balance at end of year | $ | 7,114\u00a0 | $ | 7,708\u00a0 | $ | 8,019\u00a0 |
| (Dollars in thousands) | |||||
| Confirmed obligations outstanding as of December 31, 2022 | $ | \u2014\u00a0 | |||
| Invoices confirmed during the year | 24,368\u00a0 | ||||
| Confirmed invoices paid during the year | (19,732) | ||||
| Confirmed obligations outstanding as of December 31, 2023 | $ | 4,636\u00a0 | |||
| Invoices confirmed during the year | 17,821\u00a0 | ||||
| Confirmed invoices paid during the year | (16,871) | ||||
| Confirmed obligations outstanding as of December 31, 2024 | $ | 5,586\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||||||||
| Operating lease cost | $ | 3,966\u00a0 | $ | 4,896\u00a0 | $ | 5,441\u00a0 | |||||||||||
| Finance lease cost: | |||||||||||||||||
| Amortization of lease assets | 91\u00a0 | 39\u00a0 | \u2014\u00a0 | ||||||||||||||
| Interest on lease liabilities | 27\u00a0 | 13\u00a0 | \u2014\u00a0 | ||||||||||||||
| Short-term lease cost | 130\u00a0 | 123\u00a0 | 163\u00a0 | ||||||||||||||
| Variable lease cost | 335\u00a0 | 743\u00a0 | 756\u00a0 | ||||||||||||||
| Total lease cost | $ | 4,549\u00a0 | $ | 5,814\u00a0 | $ | 6,360\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||||||||
| Cash paid for amounts included in the measurement of lease liabilities | |||||||||||||||||
| Operating cash outflows - payments on operating leases | $ | (2,815) | $ | (3,919) | $ | (4,015) | |||||||||||
| Operating cash outflows - interest payments on finance leases | (27) | (13) | \u2014\u00a0 | ||||||||||||||
| Financing cash outflows - payments on finance lease obligations | (82) | (36) | \u2014\u00a0 | ||||||||||||||
| Right-of-use assets obtained in exchange for operating lease obligations | 4,775\u00a0 | 2,621\u00a0 | 2,303\u00a0 | ||||||||||||||
| Right-of-use assets obtained in exchange for finance lease obligations | 130\u00a0 | 291\u00a0 | \u2014\u00a0 |
| December 31, | |||||||||||||||||
| 2024 | 2023 | ||||||||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||||||||
| Location | |||||||||||||||||
| Operating Leases | |||||||||||||||||
| Operating lease right-of-use assets | \u00a0 | $ | 6,261\u00a0 | $ | 5,003\u00a0 | ||||||||||||
| Current operating lease liabilities | 2,050\u00a0 | 2,568\u00a0 | |||||||||||||||
| Non-current operating lease liabilities | 4,077\u00a0 | 2,542\u00a0 | |||||||||||||||
| Total operating lease liabilities | $ | 6,127\u00a0 | $ | 5,110\u00a0 | |||||||||||||
| Finance Leases | |||||||||||||||||
| Property, plant and equipment | $ | 484\u00a0 | $ | 330\u00a0 | |||||||||||||
| Accumulated depreciation | Accumulated depreciation | 130\u00a0 | 39\u00a0 | ||||||||||||||
| Finance lease assets, net | $ | 354\u00a0 | $ | 291\u00a0 | |||||||||||||
| Other liabilities and accrued items | $ | 119\u00a0 | $ | 83\u00a0 | |||||||||||||
| Finance lease liabilities | 248\u00a0 | 210\u00a0 | |||||||||||||||
| Total principal payable on finance leases | $ | 367\u00a0 | $ | 293\u00a0 | |||||||||||||
| Weighted-Average Remaining Lease Term | |||||||||||||||||
| Operating leases | 5.1 years | 2.4 years | |||||||||||||||
| Finance leases | 3.6 years | 4.1 years | |||||||||||||||
| Weighted-Average Discount Rate | |||||||||||||||||
| Operating leases | 6.46\u00a0 | % | 6.63\u00a0 | % | |||||||||||||
| Finance leases | 7.55\u00a0 | % | 7.93\u00a0 | % |
| Finance Leases | Operating Leases | |||||||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | |||||||||||||
| 2025 | 124\u00a0 | 2,061\u00a0 | ||||||||||||
| 2026 | 124\u00a0 | 1,790\u00a0 | ||||||||||||
| 2027 | 87\u00a0 | 779\u00a0 | ||||||||||||
| 2028 | 68\u00a0 | 490\u00a0 | ||||||||||||
| 2029 | 15\u00a0 | 466\u00a0 | ||||||||||||
| 2030 and thereafter | \u2014\u00a0 | 1,854\u00a0 | ||||||||||||
| Total lease payments | $ | 418\u00a0 | $ | 7,440\u00a0 | ||||||||||
| Less: Imputed interest | (51) | (1,313) | ||||||||||||
| Present value of lease payments | $ | 367\u00a0 | $ | 6,127\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||||||||
| Operating lease cost | $ | 3,966\u00a0 | $ | 4,896\u00a0 | $ | 5,441\u00a0 | |||||||||||
| Finance lease cost: | |||||||||||||||||
| Amortization of lease assets | 91\u00a0 | 39\u00a0 | \u2014\u00a0 | ||||||||||||||
| Interest on lease liabilities | 27\u00a0 | 13\u00a0 | \u2014\u00a0 | ||||||||||||||
| Short-term lease cost | 130\u00a0 | 123\u00a0 | 163\u00a0 | ||||||||||||||
| Variable lease cost | 335\u00a0 | 743\u00a0 | 756\u00a0 | ||||||||||||||
| Total lease cost | $ | 4,549\u00a0 | $ | 5,814\u00a0 | $ | 6,360\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||||||||
| Cash paid for amounts included in the measurement of lease liabilities | |||||||||||||||||
| Operating cash outflows - payments on operating leases | $ | (2,815) | $ | (3,919) | $ | (4,015) | |||||||||||
| Operating cash outflows - interest payments on finance leases | (27) | (13) | \u2014\u00a0 | ||||||||||||||
| Financing cash outflows - payments on finance lease obligations | (82) | (36) | \u2014\u00a0 | ||||||||||||||
| Right-of-use assets obtained in exchange for operating lease obligations | 4,775\u00a0 | 2,621\u00a0 | 2,303\u00a0 | ||||||||||||||
| Right-of-use assets obtained in exchange for finance lease obligations | 130\u00a0 | 291\u00a0 | \u2014\u00a0 |
| December 31, | |||||||||||||||||
| 2024 | 2023 | ||||||||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||||||||
| Location | |||||||||||||||||
| Operating Leases | |||||||||||||||||
| Operating lease right-of-use assets | \u00a0 | $ | 6,261\u00a0 | $ | 5,003\u00a0 | ||||||||||||
| Current operating lease liabilities | 2,050\u00a0 | 2,568\u00a0 | |||||||||||||||
| Non-current operating lease liabilities | 4,077\u00a0 | 2,542\u00a0 | |||||||||||||||
| Total operating lease liabilities | $ | 6,127\u00a0 | $ | 5,110\u00a0 | |||||||||||||
| Finance Leases | |||||||||||||||||
| Property, plant and equipment | $ | 484\u00a0 | $ | 330\u00a0 | |||||||||||||
| Accumulated depreciation | Accumulated depreciation | 130\u00a0 | 39\u00a0 | ||||||||||||||
| Finance lease assets, net | $ | 354\u00a0 | $ | 291\u00a0 | |||||||||||||
| Other liabilities and accrued items | $ | 119\u00a0 | $ | 83\u00a0 | |||||||||||||
| Finance lease liabilities | 248\u00a0 | 210\u00a0 | |||||||||||||||
| Total principal payable on finance leases | $ | 367\u00a0 | $ | 293\u00a0 | |||||||||||||
| Weighted-Average Remaining Lease Term | |||||||||||||||||
| Operating leases | 5.1 years | 2.4 years | |||||||||||||||
| Finance leases | 3.6 years | 4.1 years | |||||||||||||||
| Weighted-Average Discount Rate | |||||||||||||||||
| Operating leases | 6.46\u00a0 | % | 6.63\u00a0 | % | |||||||||||||
| Finance leases | 7.55\u00a0 | % | 7.93\u00a0 | % |
| Finance Leases | Operating Leases | |||||||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | |||||||||||||
| 2025 | 124\u00a0 | 2,061\u00a0 | ||||||||||||
| 2026 | 124\u00a0 | 1,790\u00a0 | ||||||||||||
| 2027 | 87\u00a0 | 779\u00a0 | ||||||||||||
| 2028 | 68\u00a0 | 490\u00a0 | ||||||||||||
| 2029 | 15\u00a0 | 466\u00a0 | ||||||||||||
| 2030 and thereafter | \u2014\u00a0 | 1,854\u00a0 | ||||||||||||
| Total lease payments | $ | 418\u00a0 | $ | 7,440\u00a0 | ||||||||||
| Less: Imputed interest | (51) | (1,313) | ||||||||||||
| Present value of lease payments | $ | 367\u00a0 | $ | 6,127\u00a0 |
| Year Ended December 31, | |||||||||||||||||||||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||||||||||||
| (Dollars in thousands) | |||||||||||||||||||||||||||||||||||
| Service cost | $ | 960\u00a0 | $ | 942\u00a0 | $ | 1,483\u00a0 | $ | 1,053\u00a0 | $ | 1,390\u00a0 | $ | 1,220\u00a0 | |||||||||||||||||||||||
| Interest cost | 4,409\u00a0 | 617\u00a0 | 4,722\u00a0 | 870\u00a0 | 3,242\u00a0 | 227\u00a0 | |||||||||||||||||||||||||||||
| (4,729) | (1,358) | (4,353) | (1,145) | (3,960) | (640) | ||||||||||||||||||||||||||||||
| Mark-to-market (gain) loss | (1,370) | 2,423\u00a0 | (2,513) | 4,395\u00a0 | (181) | (7,801) | |||||||||||||||||||||||||||||
| Net periodic benefit (credit) cost | $ | (730) | $ | 2,624\u00a0 | $ | (661) | $ | 5,173\u00a0 | $ | 491\u00a0 | $ | (6,994) |
| \u00a0 | December 31, 2024 | December 31, 2023 | |||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||||||||
| Changes in Benefit Obligation: | |||||||||||||||||||||||
| Net benefit obligation at beginning of period | $ | 97,322\u00a0 | $ | 37,481\u00a0 | $ | 99,993\u00a0 | $ | 31,065\u00a0 | |||||||||||||||
| Service cost | 960\u00a0 | 942\u00a0 | 1,483\u00a0 | 1,053\u00a0 | |||||||||||||||||||
| Interest cost | 4,409\u00a0 | 617\u00a0 | 4,722\u00a0 | 870\u00a0 | |||||||||||||||||||
| Participant contributions | \u2014\u00a0 | 435\u00a0 | \u2014\u00a0 | 501\u00a0 | |||||||||||||||||||
| Plan settlements | \u2014\u00a0 | (3,267) | \u2014\u00a0 | (1,609) | |||||||||||||||||||
| Foreign currency exchange changes | \u2014\u00a0 | (2,748) | \u2014\u00a0 | 2,983\u00a0 | |||||||||||||||||||
| Actuarial (gain) loss | (3,550) | 1,676\u00a0 | 1,516\u00a0 | 3,694\u00a0 | |||||||||||||||||||
| Benefits paid | (9,686) | (1,091) | (10,392) | (1,076) | |||||||||||||||||||
| Net benefit obligation at end of period | $ | 89,455\u00a0 | $ | 34,045\u00a0 | $ | 97,322\u00a0 | $ | 37,481\u00a0 | |||||||||||||||
| Changes in Plan Assets: | |||||||||||||||||||||||
| Fair value of plan assets at beginning of period | $ | 78,396\u00a0 | $ | 29,981\u00a0 | $ | 80,006\u00a0 | $ | 27,708\u00a0 | |||||||||||||||
| Actual return on plan assets | 2,549\u00a0 | 611\u00a0 | 8,382\u00a0 | 645\u00a0 | |||||||||||||||||||
| Foreign currency exchange rate changes | \u2014\u00a0 | (2,172) | \u2014\u00a0 | 2,609\u00a0 | |||||||||||||||||||
| Plan settlements | \u2014\u00a0 | (3,267) | \u2014\u00a0 | (1,609) | |||||||||||||||||||
| Employer contributions | 4,385\u00a0 | 760\u00a0 | 400\u00a0 | 1,203\u00a0 | |||||||||||||||||||
| Participant contributions | \u2014\u00a0 | 435\u00a0 | \u2014\u00a0 | 501\u00a0 | |||||||||||||||||||
| Benefits paid | (9,377) | (1,006) | (10,392) | (1,076) | |||||||||||||||||||
| Fair value of plan assets at end of period | $ | 75,953\u00a0 | $ | 25,342\u00a0 | $ | 78,396\u00a0 | $ | 29,981\u00a0 | |||||||||||||||
| Funded status (underfunded): | $ | (13,502) | $ | (8,703) | $ | (18,926) | $ | (7,500) | |||||||||||||||
| Amounts recognized in the statement \u00a0\u00a0of financial position: | |||||||||||||||||||||||
| Other accrued liabilities | $ | (286) | $ | \u2014\u00a0 | $ | (324) | $ | (34) | |||||||||||||||
| Other long-term obligations | (13,216) | (8,703) | (18,602) | (7,466) | |||||||||||||||||||
| Net amount recognized | $ | (13,502) | $ | (8,703) | $ | (18,926) | $ | (7,500) |
| \u00a0 | December 31, 2024 | ||||||||||||||||||||||
| Level\u00a01 | Level\u00a02 | Level 3 | Total | ||||||||||||||||||||
| U.S. Plan Assets | |||||||||||||||||||||||
| Cash\u00a0and\u00a0cash\u00a0equivalents | $ | 696\u00a0 | $ | \u2014\u00a0 | $ | \u2014\u00a0 | $ | 696\u00a0 | |||||||||||||||
| International\u00a0Plan\u00a0Assets | |||||||||||||||||||||||
| Foreign\u00a0government\u00a0bonds | \u2014\u00a0 | 700\u00a0 | \u2014\u00a0 | 700\u00a0 | |||||||||||||||||||
| Fixed\u00a0insurance\u00a0contracts | \u2014\u00a0 | \u2014\u00a0 | 24,642\u00a0 | 24,642\u00a0 | |||||||||||||||||||
| Total international plan assets | $ | \u2014\u00a0 | $ | 700\u00a0 | $ | 24,642\u00a0 | $ | 25,342\u00a0 | |||||||||||||||
| U.S. Plan - Investments measured at net asset value | $ | 75,257\u00a0 | |||||||||||||||||||||
| Total | $ | 696\u00a0 | $ | 700\u00a0 | $ | 24,642\u00a0 | $ | 101,295\u00a0 | |||||||||||||||
| December 31, 2023 | |||||||||||||||||||||||
| Level\u00a01 | Level 2 | Level 3 | Total | ||||||||||||||||||||
| U.S. Plan Assets | |||||||||||||||||||||||
| Cash\u00a0and\u00a0cash\u00a0equivalents | $ | 710\u00a0 | $ | \u2014\u00a0 | $ | \u2014\u00a0 | $ | 710\u00a0 | |||||||||||||||
| International\u00a0Plan\u00a0Assets | |||||||||||||||||||||||
| Foreign\u00a0government\u00a0bonds | $ | \u2014\u00a0 | $ | 961\u00a0 | $ | \u2014\u00a0 | $ | 961\u00a0 | |||||||||||||||
| Fixed\u00a0insurance\u00a0contracts | \u2014\u00a0 | \u2014\u00a0 | 29,020\u00a0 | 29,020\u00a0 | |||||||||||||||||||
| Total international plan assets | $ | \u2014\u00a0 | $ | 961\u00a0 | $ | 29,020\u00a0 | $ | 29,981\u00a0 | |||||||||||||||
| U.S. Plan - Investments measured at net asset value | $ | 77,686\u00a0 | |||||||||||||||||||||
| Total | $ | 710\u00a0 | $ | 961\u00a0 | $ | 29,020\u00a0 | $ | 108,377\u00a0 |
| Fixed\u00a0Insurance Contracts | |||||
Balance at December\u00a031, 2022 | $ | 26,685\u00a0 | |||
| \u00a0\u00a0\u00a0 | 2,489\u00a0 | ||||
| \u00a0\u00a0\u00a0Distributions | (154) | ||||
Balance at December\u00a031, 2023 | 29,020\u00a0 | ||||
| \u00a0\u00a0\u00a0 | (4,241) | ||||
| \u00a0\u00a0\u00a0Distributions | (137) | ||||
Balance at December\u00a031, 2024 | $ | 24,642\u00a0 |
| Pension Benefit Obligations Key Assumptions | December\u00a031, | ||||||||||
| \u00a0 | 2024 | 2023 | |||||||||
| Weighted average assumptions to determine benefit obligations: | |||||||||||
| Discount rate | 4.29\u00a0 | % | 3.93\u00a0 | % | |||||||
| Rate\u00a0of\u00a0compensation\u00a0increase | 1.69\u00a0 | % | 1.70\u00a0 | % |
| Pension Cost Key Assumptions | |||||||||||
| Weighted average assumptions to determine net cost: | |||||||||||
| Discount rate | 3.93\u00a0 | % | 4.43\u00a0 | % | |||||||
| Expected return on plan assets | 5.88\u00a0 | % | 5.30\u00a0 | % | |||||||
| Rate of compensation increase | 1.70\u00a0 | % | 1.71\u00a0 | % |
| \u00a0 | Percentage\u00a0of\u00a0Plan\u00a0Assets \u00a0December\u00a031, 2024 | ||||||||||
| \u00a0 | U.S. | Foreign | |||||||||
| Equity securities and return seeking assets | 20\u00a0 | % | \u2014\u00a0 | % | |||||||
| Fixed income, debt securities, or cash | 80\u00a0 | % | 100\u00a0 | % | |||||||
| Total | 100\u00a0 | % | 100\u00a0 | % |
| \u00a0 | 2024 | 2023 | |||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||||||||
| Accumulated benefit obligation | $ | 89,455\u00a0 | $ | 32,311\u00a0 | $ | 97,322\u00a0 | $ | 35,772\u00a0 | |||||||||||||||
| Fair value of plan assets | 75,953\u00a0 | 25,342\u00a0 | 78,396\u00a0 | 29,981\u00a0 |
| \u00a0 | 2024 | 2023 | |||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||||||||
| Projected benefit obligation | $ | 89,455\u00a0 | $ | 34,045\u00a0 | $ | 97,322\u00a0 | $ | 37,481\u00a0 | |||||||||||||||
| Fair value of plan assets | 75,953\u00a0 | 25,342\u00a0 | 78,396\u00a0 | 29,981\u00a0 |
| U.S. | Foreign | ||||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | ||||||||||
| Expected contributions in 2025: | |||||||||||
| Expected employer contributions | $ | 1,811\u00a0 | $ | 542\u00a0 | |||||||
| Expected employee contributions | \u2014\u00a0 | \u2014\u00a0 | |||||||||
| Estimated future benefit payments reflecting expected future service for the years ending December\u00a031: | |||||||||||
| 2025 | $ | 8,986\u00a0 | $ | 1,231\u00a0 | |||||||
| 2026 | 8,906\u00a0 | 1,827\u00a0 | |||||||||
| 2027 | 8,684\u00a0 | 1,472\u00a0 | |||||||||
| 2028 | 8,476\u00a0 | 2,048\u00a0 | |||||||||
| 2029 | 8,198\u00a0 | 2,468\u00a0 | |||||||||
| Next five years | 36,215\u00a0 | 9,376\u00a0 |
| Year Ended December 31, | |||||||||||||||||||||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||||||||||||
| (Dollars in thousands) | |||||||||||||||||||||||||||||||||||
| Service cost | $ | 960\u00a0 | $ | 942\u00a0 | $ | 1,483\u00a0 | $ | 1,053\u00a0 | $ | 1,390\u00a0 | $ | 1,220\u00a0 | |||||||||||||||||||||||
| Interest cost | 4,409\u00a0 | 617\u00a0 | 4,722\u00a0 | 870\u00a0 | 3,242\u00a0 | 227\u00a0 | |||||||||||||||||||||||||||||
| (4,729) | (1,358) | (4,353) | (1,145) | (3,960) | (640) | ||||||||||||||||||||||||||||||
| Mark-to-market (gain) loss | (1,370) | 2,423\u00a0 | (2,513) | 4,395\u00a0 | (181) | (7,801) | |||||||||||||||||||||||||||||
| Net periodic benefit (credit) cost | $ | (730) | $ | 2,624\u00a0 | $ | (661) | $ | 5,173\u00a0 | $ | 491\u00a0 | $ | (6,994) |
| \u00a0 | December 31, 2024 | December 31, 2023 | |||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||||||||
| Changes in Benefit Obligation: | |||||||||||||||||||||||
| Net benefit obligation at beginning of period | $ | 97,322\u00a0 | $ | 37,481\u00a0 | $ | 99,993\u00a0 | $ | 31,065\u00a0 | |||||||||||||||
| Service cost | 960\u00a0 | 942\u00a0 | 1,483\u00a0 | 1,053\u00a0 | |||||||||||||||||||
| Interest cost | 4,409\u00a0 | 617\u00a0 | 4,722\u00a0 | 870\u00a0 | |||||||||||||||||||
| Participant contributions | \u2014\u00a0 | 435\u00a0 | \u2014\u00a0 | 501\u00a0 | |||||||||||||||||||
| Plan settlements | \u2014\u00a0 | (3,267) | \u2014\u00a0 | (1,609) | |||||||||||||||||||
| Foreign currency exchange changes | \u2014\u00a0 | (2,748) | \u2014\u00a0 | 2,983\u00a0 | |||||||||||||||||||
| Actuarial (gain) loss | (3,550) | 1,676\u00a0 | 1,516\u00a0 | 3,694\u00a0 | |||||||||||||||||||
| Benefits paid | (9,686) | (1,091) | (10,392) | (1,076) | |||||||||||||||||||
| Net benefit obligation at end of period | $ | 89,455\u00a0 | $ | 34,045\u00a0 | $ | 97,322\u00a0 | $ | 37,481\u00a0 | |||||||||||||||
| Changes in Plan Assets: | |||||||||||||||||||||||
| Fair value of plan assets at beginning of period | $ | 78,396\u00a0 | $ | 29,981\u00a0 | $ | 80,006\u00a0 | $ | 27,708\u00a0 | |||||||||||||||
| Actual return on plan assets | 2,549\u00a0 | 611\u00a0 | 8,382\u00a0 | 645\u00a0 | |||||||||||||||||||
| Foreign currency exchange rate changes | \u2014\u00a0 | (2,172) | \u2014\u00a0 | 2,609\u00a0 | |||||||||||||||||||
| Plan settlements | \u2014\u00a0 | (3,267) | \u2014\u00a0 | (1,609) | |||||||||||||||||||
| Employer contributions | 4,385\u00a0 | 760\u00a0 | 400\u00a0 | 1,203\u00a0 | |||||||||||||||||||
| Participant contributions | \u2014\u00a0 | 435\u00a0 | \u2014\u00a0 | 501\u00a0 | |||||||||||||||||||
| Benefits paid | (9,377) | (1,006) | (10,392) | (1,076) | |||||||||||||||||||
| Fair value of plan assets at end of period | $ | 75,953\u00a0 | $ | 25,342\u00a0 | $ | 78,396\u00a0 | $ | 29,981\u00a0 | |||||||||||||||
| Funded status (underfunded): | $ | (13,502) | $ | (8,703) | $ | (18,926) | $ | (7,500) | |||||||||||||||
| Amounts recognized in the statement \u00a0\u00a0of financial position: | |||||||||||||||||||||||
| Other accrued liabilities | $ | (286) | $ | \u2014\u00a0 | $ | (324) | $ | (34) | |||||||||||||||
| Other long-term obligations | (13,216) | (8,703) | (18,602) | (7,466) | |||||||||||||||||||
| Net amount recognized | $ | (13,502) | $ | (8,703) | $ | (18,926) | $ | (7,500) |
| \u00a0 | December 31, 2024 | ||||||||||||||||||||||
| Level\u00a01 | Level\u00a02 | Level 3 | Total | ||||||||||||||||||||
| U.S. Plan Assets | |||||||||||||||||||||||
| Cash\u00a0and\u00a0cash\u00a0equivalents | $ | 696\u00a0 | $ | \u2014\u00a0 | $ | \u2014\u00a0 | $ | 696\u00a0 | |||||||||||||||
| International\u00a0Plan\u00a0Assets | |||||||||||||||||||||||
| Foreign\u00a0government\u00a0bonds | \u2014\u00a0 | 700\u00a0 | \u2014\u00a0 | 700\u00a0 | |||||||||||||||||||
| Fixed\u00a0insurance\u00a0contracts | \u2014\u00a0 | \u2014\u00a0 | 24,642\u00a0 | 24,642\u00a0 | |||||||||||||||||||
| Total international plan assets | $ | \u2014\u00a0 | $ | 700\u00a0 | $ | 24,642\u00a0 | $ | 25,342\u00a0 | |||||||||||||||
| U.S. Plan - Investments measured at net asset value | $ | 75,257\u00a0 | |||||||||||||||||||||
| Total | $ | 696\u00a0 | $ | 700\u00a0 | $ | 24,642\u00a0 | $ | 101,295\u00a0 | |||||||||||||||
| December 31, 2023 | |||||||||||||||||||||||
| Level\u00a01 | Level 2 | Level 3 | Total | ||||||||||||||||||||
| U.S. Plan Assets | |||||||||||||||||||||||
| Cash\u00a0and\u00a0cash\u00a0equivalents | $ | 710\u00a0 | $ | \u2014\u00a0 | $ | \u2014\u00a0 | $ | 710\u00a0 | |||||||||||||||
| International\u00a0Plan\u00a0Assets | |||||||||||||||||||||||
| Foreign\u00a0government\u00a0bonds | $ | \u2014\u00a0 | $ | 961\u00a0 | $ | \u2014\u00a0 | $ | 961\u00a0 | |||||||||||||||
| Fixed\u00a0insurance\u00a0contracts | \u2014\u00a0 | \u2014\u00a0 | 29,020\u00a0 | 29,020\u00a0 | |||||||||||||||||||
| Total international plan assets | $ | \u2014\u00a0 | $ | 961\u00a0 | $ | 29,020\u00a0 | $ | 29,981\u00a0 | |||||||||||||||
| U.S. Plan - Investments measured at net asset value | $ | 77,686\u00a0 | |||||||||||||||||||||
| Total | $ | 710\u00a0 | $ | 961\u00a0 | $ | 29,020\u00a0 | $ | 108,377\u00a0 |
| Fixed\u00a0Insurance Contracts | |||||
Balance at December\u00a031, 2022 | $ | 26,685\u00a0 | |||
| \u00a0\u00a0\u00a0 | 2,489\u00a0 | ||||
| \u00a0\u00a0\u00a0Distributions | (154) | ||||
Balance at December\u00a031, 2023 | 29,020\u00a0 | ||||
| \u00a0\u00a0\u00a0 | (4,241) | ||||
| \u00a0\u00a0\u00a0Distributions | (137) | ||||
Balance at December\u00a031, 2024 | $ | 24,642\u00a0 |
| Pension Benefit Obligations Key Assumptions | December\u00a031, | ||||||||||
| \u00a0 | 2024 | 2023 | |||||||||
| Weighted average assumptions to determine benefit obligations: | |||||||||||
| Discount rate | 4.29\u00a0 | % | 3.93\u00a0 | % | |||||||
| Rate\u00a0of\u00a0compensation\u00a0increase | 1.69\u00a0 | % | 1.70\u00a0 | % |
| Pension Cost Key Assumptions | |||||||||||
| Weighted average assumptions to determine net cost: | |||||||||||
| Discount rate | 3.93\u00a0 | % | 4.43\u00a0 | % | |||||||
| Expected return on plan assets | 5.88\u00a0 | % | 5.30\u00a0 | % | |||||||
| Rate of compensation increase | 1.70\u00a0 | % | 1.71\u00a0 | % |
| \u00a0 | Percentage\u00a0of\u00a0Plan\u00a0Assets \u00a0December\u00a031, 2024 | ||||||||||
| \u00a0 | U.S. | Foreign | |||||||||
| Equity securities and return seeking assets | 20\u00a0 | % | \u2014\u00a0 | % | |||||||
| Fixed income, debt securities, or cash | 80\u00a0 | % | 100\u00a0 | % | |||||||
| Total | 100\u00a0 | % | 100\u00a0 | % |
| \u00a0 | 2024 | 2023 | |||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||||||||
| Accumulated benefit obligation | $ | 89,455\u00a0 | $ | 32,311\u00a0 | $ | 97,322\u00a0 | $ | 35,772\u00a0 | |||||||||||||||
| Fair value of plan assets | 75,953\u00a0 | 25,342\u00a0 | 78,396\u00a0 | 29,981\u00a0 |
| \u00a0 | 2024 | 2023 | |||||||||||||||||||||
| \u00a0 | U.S. | Foreign | U.S. | Foreign | |||||||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||||||||
| Projected benefit obligation | $ | 89,455\u00a0 | $ | 34,045\u00a0 | $ | 97,322\u00a0 | $ | 37,481\u00a0 | |||||||||||||||
| Fair value of plan assets | 75,953\u00a0 | 25,342\u00a0 | 78,396\u00a0 | 29,981\u00a0 |
| U.S. | Foreign | ||||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | ||||||||||
| Expected contributions in 2025: | |||||||||||
| Expected employer contributions | $ | 1,811\u00a0 | $ | 542\u00a0 | |||||||
| Expected employee contributions | \u2014\u00a0 | \u2014\u00a0 | |||||||||
| Estimated future benefit payments reflecting expected future service for the years ending December\u00a031: | |||||||||||
| 2025 | $ | 8,986\u00a0 | $ | 1,231\u00a0 | |||||||
| 2026 | 8,906\u00a0 | 1,827\u00a0 | |||||||||
| 2027 | 8,684\u00a0 | 1,472\u00a0 | |||||||||
| 2028 | 8,476\u00a0 | 2,048\u00a0 | |||||||||
| 2029 | 8,198\u00a0 | 2,468\u00a0 | |||||||||
| Next five years | 36,215\u00a0 | 9,376\u00a0 |
| \u00a0 | |||||
| (Dollars in thousands) | |||||
Balance as of December\u00a031, 2022 | $ | 820\u00a0 | |||
| Product warranty charges/adjustments | 25\u00a0 | ||||
| Payments and settlements | (768) | ||||
Balance as of December\u00a031, 2023 | $ | 77\u00a0 | |||
| Product warranty charges/adjustments | 322\u00a0 | ||||
| Payments and settlements | (150) | ||||
Balance as of December\u00a031, 2024 | $ | 249\u00a0 |
| \u00a0 | |||||
| (Dollars in thousands) | |||||
Balance as of December\u00a031, 2022 | $ | 820\u00a0 | |||
| Product warranty charges/adjustments | 25\u00a0 | ||||
| Payments and settlements | (768) | ||||
Balance as of December\u00a031, 2023 | $ | 77\u00a0 | |||
| Product warranty charges/adjustments | 322\u00a0 | ||||
| Payments and settlements | (150) | ||||
Balance as of December\u00a031, 2024 | $ | 249\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| \u00a0 | 2024 | 2023 | 2022 | ||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| U.S. | $ | (79,339) | $ | (111,821) | $ | 55,107\u00a0 | |||||||||||
| Foreign | (73,929) | (161,943) | 397,211\u00a0 | ||||||||||||||
| (Loss) income before income taxes | $ | (153,268) | $ | (273,764) | $ | 452,318\u00a0 |
| \u00a0 | Year Ended December 31, | ||||||||||||||||
| \u00a0 | 2024 | 2023 | 2022 | ||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| U.S. income taxes: | |||||||||||||||||
| Current | $ | 153\u00a0 | $ | (129) | $ | 3,590\u00a0 | |||||||||||
| Deferred | (17,930) | (12,643) | 13,302\u00a0 | ||||||||||||||
| (17,777) | (12,772) | 16,892\u00a0 | |||||||||||||||
| Foreign income taxes: | |||||||||||||||||
| Current | 5,378\u00a0 | 9,738\u00a0 | 48,744\u00a0 | ||||||||||||||
| Deferred | (9,704) | (15,480) | 3,720\u00a0 | ||||||||||||||
| (4,326) | (5,742) | 52,464\u00a0 | |||||||||||||||
| Income tax (benefit) expense | $ | (22,103) | $ | (18,514) | $ | 69,356\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| \u00a0 | 2024 | 2023 | 2022 | ||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Tax at statutory U.S. federal rate | $ | (32,190) | $ | (57,490) | $ | 94,987\u00a0 | |||||||||||
| Impact of U.S. Tax Cuts and Jobs Act of 2017 - GILTI | 195\u00a0 | 1,041\u00a0 | 38,153\u00a0 | ||||||||||||||
| Impact of Tax Receivable Agreement | (26) | 91\u00a0 | (39) | ||||||||||||||
| Valuation allowance | 10,396\u00a0 | (282) | (1,259) | ||||||||||||||
| State taxes, net of federal tax benefit | (10,054) | 818\u00a0 | 2,182\u00a0 | ||||||||||||||
| U.S. tax impact of foreign earnings (net of foreign tax credits) | 587\u00a0 | 311\u00a0 | 348\u00a0 | ||||||||||||||
| Establishment/resolution of uncertain tax positions | \u2014\u00a0 | (36) | (40) | ||||||||||||||
| Adjustment for foreign income taxed at different rates | 11,476\u00a0 | 16,666\u00a0 | (25,656) | ||||||||||||||
| Foreign tax credits | \u2014\u00a0 | (2,534) | (34,264) | ||||||||||||||
| Change-in-Control-related compensation | \u2014\u00a0 | \u2014\u00a0 | (1,432) | ||||||||||||||
| Impact of non-deductible goodwill impairment | \u2014\u00a0 | 24,570\u00a0 | \u2014\u00a0 | ||||||||||||||
| Other | (2,487) | (1,669) | (3,624) | ||||||||||||||
| Income tax (benefit) expense | $ | (22,103) | $ | (18,514) | $ | 69,356\u00a0 |
| \u00a0 | December\u00a031, | ||||||||||
| \u00a0 | 2024 | 2023 | |||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | ||||||||||
| Deferred tax assets: | |||||||||||
| Post-employment and other employee benefits | $ | 15,240\u00a0 | $ | 18,088\u00a0 | |||||||
| Foreign tax credit and other carryforwards | 81,682\u00a0 | 40,172\u00a0 | |||||||||
| Capitalized research and experimental costs | 212\u00a0 | 212\u00a0 | |||||||||
| Environmental reserves | \u2014\u00a0 | 1,058\u00a0 | |||||||||
| Inventory adjustments | 4,936\u00a0 | 7,710\u00a0 | |||||||||
| Long-term contract option amortization | 845\u00a0 | 881\u00a0 | |||||||||
| Other | 4,406\u00a0 | 1,198\u00a0 | |||||||||
| Total gross deferred tax assets | 107,321\u00a0 | 69,319\u00a0 | |||||||||
| Less: valuation allowance | (19,308) | (8,956) | |||||||||
| Total deferred tax assets | 88,013\u00a0 | 60,363\u00a0 | |||||||||
| Deferred tax liabilities: | |||||||||||
| Fixed assets | $ | 50,247\u00a0 | $ | 51,474\u00a0 | |||||||
| Goodwill and acquired intangibles | 6,676\u00a0 | 6,418\u00a0 | |||||||||
| Mark-to-market hedges | \u2014\u00a0 | 1,403\u00a0 | |||||||||
| Other | 1,922\u00a0 | 2,732\u00a0 | |||||||||
| Total deferred tax liabilities | 58,845\u00a0 | 62,027\u00a0 | |||||||||
| Net deferred tax asset (liability) | $ | 29,168\u00a0 | $ | (1,664) |
| (Dollars in thousands) | |||||
| Balance as of December 31, 2021 | $ | 10,550\u00a0 | |||
| Credited to income | (1,259) | ||||
| Translation adjustment | (22) | ||||
Balance as of December\u00a031, 2022 | $ | 9,269\u00a0 | |||
| Credited to income | (268) | ||||
| Translation adjustment | (45) | ||||
Balance as of December\u00a031, 2023 | $ | 8,956\u00a0 | |||
| Charged to income | 10,396\u00a0 | ||||
| Translation adjustment | (44) | ||||
Balance as of December\u00a031, 2024 | $ | 19,308\u00a0 |
| (Dollars in thousands) | |||||
Balance as of December\u00a031, 2022 | $ | 36\u00a0 | |||
| Lapse of statute of limitations | (36) | ||||
| \u00a0\u00a0\u00a0Foreign currency impact | \u2014\u00a0 | ||||
Balance as of December\u00a031, 2023 | $ | \u2014\u00a0 | |||
| \u00a0\u00a0\u00a0Lapse of statute of limitations | \u2014\u00a0 | ||||
| \u00a0\u00a0\u00a0Foreign currency impact | \u2014\u00a0 | ||||
Balance as of December\u00a031, 2024 | $ | \u2014\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| \u00a0 | 2024 | 2023 | 2022 | ||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| U.S. | $ | (79,339) | $ | (111,821) | $ | 55,107\u00a0 | |||||||||||
| Foreign | (73,929) | (161,943) | 397,211\u00a0 | ||||||||||||||
| (Loss) income before income taxes | $ | (153,268) | $ | (273,764) | $ | 452,318\u00a0 |
| \u00a0 | Year Ended December 31, | ||||||||||||||||
| \u00a0 | 2024 | 2023 | 2022 | ||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| U.S. income taxes: | |||||||||||||||||
| Current | $ | 153\u00a0 | $ | (129) | $ | 3,590\u00a0 | |||||||||||
| Deferred | (17,930) | (12,643) | 13,302\u00a0 | ||||||||||||||
| (17,777) | (12,772) | 16,892\u00a0 | |||||||||||||||
| Foreign income taxes: | |||||||||||||||||
| Current | 5,378\u00a0 | 9,738\u00a0 | 48,744\u00a0 | ||||||||||||||
| Deferred | (9,704) | (15,480) | 3,720\u00a0 | ||||||||||||||
| (4,326) | (5,742) | 52,464\u00a0 | |||||||||||||||
| Income tax (benefit) expense | $ | (22,103) | $ | (18,514) | $ | 69,356\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| \u00a0 | 2024 | 2023 | 2022 | ||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Tax at statutory U.S. federal rate | $ | (32,190) | $ | (57,490) | $ | 94,987\u00a0 | |||||||||||
| Impact of U.S. Tax Cuts and Jobs Act of 2017 - GILTI | 195\u00a0 | 1,041\u00a0 | 38,153\u00a0 | ||||||||||||||
| Impact of Tax Receivable Agreement | (26) | 91\u00a0 | (39) | ||||||||||||||
| Valuation allowance | 10,396\u00a0 | (282) | (1,259) | ||||||||||||||
| State taxes, net of federal tax benefit | (10,054) | 818\u00a0 | 2,182\u00a0 | ||||||||||||||
| U.S. tax impact of foreign earnings (net of foreign tax credits) | 587\u00a0 | 311\u00a0 | 348\u00a0 | ||||||||||||||
| Establishment/resolution of uncertain tax positions | \u2014\u00a0 | (36) | (40) | ||||||||||||||
| Adjustment for foreign income taxed at different rates | 11,476\u00a0 | 16,666\u00a0 | (25,656) | ||||||||||||||
| Foreign tax credits | \u2014\u00a0 | (2,534) | (34,264) | ||||||||||||||
| Change-in-Control-related compensation | \u2014\u00a0 | \u2014\u00a0 | (1,432) | ||||||||||||||
| Impact of non-deductible goodwill impairment | \u2014\u00a0 | 24,570\u00a0 | \u2014\u00a0 | ||||||||||||||
| Other | (2,487) | (1,669) | (3,624) | ||||||||||||||
| Income tax (benefit) expense | $ | (22,103) | $ | (18,514) | $ | 69,356\u00a0 |
| \u00a0 | December\u00a031, | ||||||||||
| \u00a0 | 2024 | 2023 | |||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | ||||||||||
| Deferred tax assets: | |||||||||||
| Post-employment and other employee benefits | $ | 15,240\u00a0 | $ | 18,088\u00a0 | |||||||
| Foreign tax credit and other carryforwards | 81,682\u00a0 | 40,172\u00a0 | |||||||||
| Capitalized research and experimental costs | 212\u00a0 | 212\u00a0 | |||||||||
| Environmental reserves | \u2014\u00a0 | 1,058\u00a0 | |||||||||
| Inventory adjustments | 4,936\u00a0 | 7,710\u00a0 | |||||||||
| Long-term contract option amortization | 845\u00a0 | 881\u00a0 | |||||||||
| Other | 4,406\u00a0 | 1,198\u00a0 | |||||||||
| Total gross deferred tax assets | 107,321\u00a0 | 69,319\u00a0 | |||||||||
| Less: valuation allowance | (19,308) | (8,956) | |||||||||
| Total deferred tax assets | 88,013\u00a0 | 60,363\u00a0 | |||||||||
| Deferred tax liabilities: | |||||||||||
| Fixed assets | $ | 50,247\u00a0 | $ | 51,474\u00a0 | |||||||
| Goodwill and acquired intangibles | 6,676\u00a0 | 6,418\u00a0 | |||||||||
| Mark-to-market hedges | \u2014\u00a0 | 1,403\u00a0 | |||||||||
| Other | 1,922\u00a0 | 2,732\u00a0 | |||||||||
| Total deferred tax liabilities | 58,845\u00a0 | 62,027\u00a0 | |||||||||
| Net deferred tax asset (liability) | $ | 29,168\u00a0 | $ | (1,664) |
| (Dollars in thousands) | |||||
| Balance as of December 31, 2021 | $ | 10,550\u00a0 | |||
| Credited to income | (1,259) | ||||
| Translation adjustment | (22) | ||||
Balance as of December\u00a031, 2022 | $ | 9,269\u00a0 | |||
| Credited to income | (268) | ||||
| Translation adjustment | (45) | ||||
Balance as of December\u00a031, 2023 | $ | 8,956\u00a0 | |||
| Charged to income | 10,396\u00a0 | ||||
| Translation adjustment | (44) | ||||
Balance as of December\u00a031, 2024 | $ | 19,308\u00a0 |
| (Dollars in thousands) | |||||
Balance as of December\u00a031, 2022 | $ | 36\u00a0 | |||
| Lapse of statute of limitations | (36) | ||||
| \u00a0\u00a0\u00a0Foreign currency impact | \u2014\u00a0 | ||||
Balance as of December\u00a031, 2023 | $ | \u2014\u00a0 | |||
| \u00a0\u00a0\u00a0Lapse of statute of limitations | \u2014\u00a0 | ||||
| \u00a0\u00a0\u00a0Foreign currency impact | \u2014\u00a0 | ||||
Balance as of December\u00a031, 2024 | $ | \u2014\u00a0 |
| \u00a0 | December 31, 2024 | December 31, 2023 | |||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | ||||||||||
| Foreign currency translation adjustments, net of tax | $ | (43,573) | $ | (19,188) | |||||||
| Commodities, interest rate and foreign currency derivatives, net of tax | 214\u00a0 | 7,730\u00a0 | |||||||||
| Total AOCL | $ | (43,359) | $ | (11,458) |
| \u00a0 | December 31, 2024 | December 31, 2023 | |||||||||
| \u00a0 | (Dollars\u00a0in\u00a0thousands) | ||||||||||
| Foreign currency translation adjustments, net of tax | $ | (43,573) | $ | (19,188) | |||||||
| Commodities, interest rate and foreign currency derivatives, net of tax | 214\u00a0 | 7,730\u00a0 | |||||||||
| Total AOCL | $ | (43,359) | $ | (11,458) |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars in thousands, except per share amounts) | |||||||||||||||||
| Numerator for basic and diluted (loss) earnings per share: | |||||||||||||||||
| Net (loss) income | $ | (131,165) | $ | (255,250) | $ | 382,962\u00a0 | |||||||||||
| Denominator: | |||||||||||||||||
| Weighted average common shares outstanding for basic calculation | 257,667,125\u00a0 | 257,042,843\u00a0 | 258,781,843\u00a0 | ||||||||||||||
| Add: Effect of equity awards | \u2014\u00a0 | \u2014\u00a0 | 9,385\u00a0 | ||||||||||||||
| Weighted average common shares outstanding for diluted calculation | 257,667,125\u00a0 | 257,042,843\u00a0 | 258,791,228\u00a0 | ||||||||||||||
| Basic (loss) earnings per share | $ | (0.51) | $ | (0.99) | $ | 1.48\u00a0 | |||||||||||
| Diluted (loss) earnings per share | $ | (0.51) | $ | (0.99) | $ | 1.48\u00a0 |
| Year Ended December 31, | |||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| (Dollars in thousands, except per share amounts) | |||||||||||||||||
| Numerator for basic and diluted (loss) earnings per share: | |||||||||||||||||
| Net (loss) income | $ | (131,165) | $ | (255,250) | $ | 382,962\u00a0 | |||||||||||
| Denominator: | |||||||||||||||||
| Weighted average common shares outstanding for basic calculation | 257,667,125\u00a0 | 257,042,843\u00a0 | 258,781,843\u00a0 | ||||||||||||||
| Add: Effect of equity awards | \u2014\u00a0 | \u2014\u00a0 | 9,385\u00a0 | ||||||||||||||
| Weighted average common shares outstanding for diluted calculation | 257,667,125\u00a0 | 257,042,843\u00a0 | 258,791,228\u00a0 | ||||||||||||||
| Basic (loss) earnings per share | $ | (0.51) | $ | (0.99) | $ | 1.48\u00a0 | |||||||||||
| Diluted (loss) earnings per share | $ | (0.51) | $ | (0.99) | $ | 1.48\u00a0 |
| \u00a0 | Year Ended December 31, | ||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Non-service pension and other post-employment expense (income) | $ | 344\u00a0 | $ | 3,771\u00a0 | $ | (9,950) | |||||||||||
| Bank charges | 783\u00a0 | 757\u00a0 | 938\u00a0 | ||||||||||||||
| Non-cash (gains) losses on foreign currency remeasurement | (1,949) | 710\u00a0 | 28\u00a0 | ||||||||||||||
| Other | (747) | (559) | (1,163) | ||||||||||||||
| Total other (income) expense, net | $ | (1,569) | $ | 4,679\u00a0 | $ | (10,147) |
| \u00a0 | Year Ended December 31, | ||||||||||||||||
| 2024 | 2023 | 2022 | |||||||||||||||
| \u00a0 | (Dollars in thousands) | ||||||||||||||||
| Non-service pension and other post-employment expense (income) | $ | 344\u00a0 | $ | 3,771\u00a0 | $ | (9,950) | |||||||||||
| Bank charges | 783\u00a0 | 757\u00a0 | 938\u00a0 | ||||||||||||||
| Non-cash (gains) losses on foreign currency remeasurement | (1,949) | 710\u00a0 | 28\u00a0 | ||||||||||||||
| Other | (747) | (559) | (1,163) | ||||||||||||||
| Total other (income) expense, net | $ | (1,569) | $ | 4,679\u00a0 | $ | (10,147) |
| Year Ended December 31, | |||||||||||
| 2024 | 2023 | ||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||
| Recorded in Cost of Goods Sold | |||||||||||
| Inventory write-offs | $ | 2,202\u00a0 | $ | \u2014\u00a0 | |||||||
| Fixed asset write-offs | 453\u00a0 | \u2014\u00a0 | |||||||||
| Total rationalization-related expenses | $ | 2,655\u00a0 | $ | \u2014\u00a0 | |||||||
| Recorded in Rationalization Expenses | |||||||||||
| Severance and related costs | $ | 2,814\u00a0 | $ | \u2014\u00a0 | |||||||
| Contract terminations | 342\u00a0 | \u2014\u00a0 | |||||||||
| Total rationalization expenses | $ | 3,156\u00a0 | $ | \u2014\u00a0 |
| Balance Sheet Line Item | |||||||||||
| Other Accrued Liabilities | Other Long-Term Obligations | ||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||
| Balance as of December 31, 2023 | $ | \u2014\u00a0 | $ | \u2014\u00a0 | |||||||
| Charges incurred | 2,479\u00a0 | 677\u00a0 | |||||||||
| Payments and settlements | (2,161) | (15) | |||||||||
| Adjustments | 367\u00a0 | (370) | |||||||||
| Balance as of December 31, 2024 | $ | 685\u00a0 | $ | 292\u00a0 |
| Year Ended December 31, | |||||||||||
| 2024 | 2023 | ||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||
| Recorded in Cost of Goods Sold | |||||||||||
| Inventory write-offs | $ | 2,202\u00a0 | $ | \u2014\u00a0 | |||||||
| Fixed asset write-offs | 453\u00a0 | \u2014\u00a0 | |||||||||
| Total rationalization-related expenses | $ | 2,655\u00a0 | $ | \u2014\u00a0 | |||||||
| Recorded in Rationalization Expenses | |||||||||||
| Severance and related costs | $ | 2,814\u00a0 | $ | \u2014\u00a0 | |||||||
| Contract terminations | 342\u00a0 | \u2014\u00a0 | |||||||||
| Total rationalization expenses | $ | 3,156\u00a0 | $ | \u2014\u00a0 |
| Balance Sheet Line Item | |||||||||||
| Other Accrued Liabilities | Other Long-Term Obligations | ||||||||||
| (Dollars\u00a0in\u00a0thousands) | |||||||||||
| Balance as of December 31, 2023 | $ | \u2014\u00a0 | $ | \u2014\u00a0 | |||||||
| Charges incurred | 2,479\u00a0 | 677\u00a0 | |||||||||
| Payments and settlements | (2,161) | (15) | |||||||||
| Adjustments | 367\u00a0 | (370) | |||||||||
| Balance as of December 31, 2024 | $ | 685\u00a0 | $ | 292\u00a0 |