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Financial Instruments and Derivatives - Additional Information (Details) MMBTU in Millions |  |  | 1 Months Ended | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
May 21, 2021 USD ($) | May 13, 2021 USD ($) | Mar. 31, 2020 USD ($) | Oct. 03, 2021 USD ($) MMBTU T | Sep. 27, 2020 USD ($) | May 25, 2021 EUR (€) | Apr. 28, 2021 USD ($) | Apr. 07, 2021 EUR (€) | Dec. 31, 2020 USD ($) | Jan. 31, 2020 USD ($)
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from foreign exchange forward contracts and interest rate swaps |  |  |  | $ 4,387,000 | $ 14,480,000 |  |  |  |  |
Total fair value of other derivatives not designated as hedging instruments |  |  |  | $ 3,117,000 |  |  |  |  | $ 599,000 |
1.0% Euro loan due May 2021 |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate (percent) |  |  |  | 1.00% |  | 1.00% |  |  |  |
Debt principal | € |  |  |  |  |  | € 150,000,000 |  |  |  |
5.75% debentures due November 2040 |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Interest rate (percent) |  |  |  | 5.75% |  |  | 5.75% |  |  |
Amount offered to be repurchased |  |  |  |  |  |  | $ 300,000,000 |  |  |
Cash Flow Hedging | Derivatives Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Fair value of commodity cash flow hedges, gain (loss) |  |  |  | $ 7,530,000 |  |  |  |  | (647,000) |
Commodity gain (loss) expected to be reclassified to the income statement during the next 12 months |  |  |  | 4,690,000 |  |  |  |  |  |
Fair value of foreign currency cash flow hedges, gain (loss) |  |  |  | 131,000 |  |  |  |  | 555,000 |
Foreign currency gain (loss) expected to be reclassified to the income statement during the next 12 months |  |  |  | $ 131,000 |  |  |  |  |  |
Natural Gas Swaps |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Approximate amount of commodity covered by swap contracts outstanding (in MMBTUs) | MMBTU |  |  |  | 4.5 |  |  |  |  |  |
Anticipated usage percentage covered by a swap contract for the current fiscal year (percent) |  |  |  | 66.00% |  |  |  |  |  |
Anticipated usage percentage covered by a swap contract for the next fiscal year (percent) |  |  |  | 42.00% |  |  |  |  |  |
Natural Gas Swaps | Derivatives Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Approximate amount of commodity covered by swap contracts outstanding (in MMBTUs) | MMBTU |  |  |  | 1.6 |  |  |  |  |  |
Anticipated usage percentage covered by a swap contract for the next fiscal year (percent) |  |  |  | 21.00% |  |  |  |  |  |
Natural Gas Swaps | Cash Flow Hedging | Derivatives Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Approximate amount of commodity covered by swap contracts outstanding (in MMBTUs) | MMBTU |  |  |  | 2.9 |  |  |  |  |  |
Anticipated usage percentage covered by a swap contract for the current fiscal year (percent) |  |  |  | 66.00% |  |  |  |  |  |
Anticipated usage percentage covered by a swap contract for the next fiscal year (percent) |  |  |  | 21.00% |  |  |  |  |  |
Aluminum Swaps | Cash Flow Hedging | Derivatives Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Anticipated usage percentage covered by a swap contract for the current fiscal year (percent) |  |  |  | 53.00% |  |  |  |  |  |
Approximate amount of commodity covered by swap contracts outstanding (in tons) | T |  |  |  | 904 |  |  |  |  |  |
Forward contracts | Cash Flow Hedging | Derivatives Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Fair value of foreign currency cash flow hedges, gain (loss) |  |  |  | $ (525,000) |  |  |  |  | $ 47,000 |
Foreign currency gain (loss) expected to be reclassified to the income statement during the next 12 months |  |  |  | (522,000) |  |  |  |  |  |
Foreign currency gain (loss) reclassified to the income statement |  |  |  | $ 42,000 |  |  |  |  |  |
Cross-currency swap |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount | € |  |  |  |  |  |  |  | € 150,000,000 |  |
Gain (loss) on derivative | $ 4,387,000 |  |  |  |  |  |  |  |  |
Cross-currency swap | Net Investment Hedge | Derivatives Designated as Hedging Instruments |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  |  |  |  | $ 250,000,000
Proceeds from foreign exchange forward contracts and interest rate swaps |  |  | $ 14,480,000 |  |  |  |  |  |  |
Tax provision on foreign currency translation gain |  |  | $ 7,581,000 |  |  |  |  |  |  |
Reverse Treasury Lock Contract |  |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  | $ 100,000,000 |  |  |
Gain (loss) on derivative |  | $ (1,356,000) |  |  |  |  |  |  |  |

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