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Debt - Narrative (Details)			1 Months Ended
	Oct. 01, 2024 USD ($)	Nov. 02, 2021 USD ($)	Apr. 30, 2021 USD ($) $ / shares	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 09, 2022 USD ($)	Sep. 28, 2022 USD ($)	Jun. 14, 2022 USD ($)	Feb. 04, 2022 USD ($)	Nov. 30, 2013 USD ($)
Senior secured notes, 7.5% | Senior notes
Line of Credit Facility [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
Senior secured notes, 7.5% | Senior notes | Level 2
Line of Credit Facility [Line Items]
Fair value of debt instrument				$ 254,100,000
Senior convertible notes, 2.75% | Senior notes
Line of Credit Facility [Line Items]
Stated interest rate, percentage			2.75%	2.75%
Face amount			$ 86,300,000
Percentage of principal amount redeemed			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
Senior convertible notes, 2.75% | Senior notes | Level 2
Line of Credit Facility [Line Items]
Fair value of debt instrument				$ 103,300,000
U.S. revolving credit facility | U.S. revolving credit facility
Line of Credit Facility [Line Items]
Stated interest rate, percentage				8.00%
Credit facility maximum amount								$ 250,000,000.0
Outstanding borrowings				$ 19,600,000
Outstanding letters of credit issued				47,300,000
Credit facility maximum amount				$ 250,000,000.0
U.S. revolving credit facility | Letter of credit
Line of Credit Facility [Line Items]
Letter of credit sub-facility amount								$ 150,000,000.0
U.S. revolving credit facility | Foreign line of credit
Line of Credit Facility [Line Items]
Stated interest rate, percentage				7.82%
Credit facility maximum amount				$ 100,000,000.0			$ 100,000,000.0			$ 50,000,000
Outstanding borrowings				0
Outstanding letters of credit issued				0
Credit facility maximum amount									$ 80,000,000
Casthouse Facility
Line of Credit Facility [Line Items]
Credit facility maximum amount		$ 130,000,000
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				$ 117,700,000
Casthouse Facility | Foreign line of credit
Line of Credit Facility [Line Items]
Stated interest rate, percentage				8.04%
Secured debt				$ 108,700,000	$ 114,200,000
Vlissingen Credit Facility | Foreign line of credit
Line of Credit Facility [Line Items]
Stated interest rate, percentage	8.75%			7.98%
Face amount						$ 90,000,000
Credit facility maximum amount	$ 90,000,000
Term extension	2 years
Debt instrument, basis spread on variable rate	3.687%
Secured debt				$ 10,000,000.0	$ 10,000,000.0
Vlissingen Credit Facility | Foreign line of credit | Maximum
Line of Credit Facility [Line Items]
Variable interest rate	9.00%
Vlissingen Credit Facility | Foreign line of credit | Minimum
Line of Credit Facility [Line Items]
Variable interest rate	7.00%
Industrial revenue bonds, variable
Line of Credit Facility [Line Items]
Maximum variable interest rate				12.00%
Surety Bond
Line of Credit Facility [Line Items]
Loss contingency accrual				$ 6,600,000

X

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Debt Instrument, Periodic Payment, Percentage To Be Paid Before Termination Date

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage of principal amount of debt redeemed.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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