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Debt - Narrative (Details) $ / shares in Units, € in Millions				12 Months Ended
	Nov. 02, 2021 USD ($)	Apr. 14, 2021 USD ($)	Apr. 09, 2021 USD ($) $ / shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 EUR (€)	Dec. 09, 2022 USD ($)	Sep. 30, 2022 EUR (€)	Sep. 28, 2022 USD ($)	Jun. 14, 2022 USD ($)	Feb. 04, 2022 USD ($)	Nov. 30, 2013 USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of Senior Notes due 2028				$ 0	$ 0	$ 250,000,000.0
Proceeds from issuance of Convertible Senior Notes				$ 0	0	$ 86,300,000
U.S revolving credit facility
Debt Instrument [Line Items]
Credit facility face amount											$ 250,000,000.0
Letter of Credit
Debt Instrument [Line Items]
Credit facility face amount											$ 150,000,000
Senior Secured Notes, 7.5% | Senior Notes
Debt Instrument [Line Items]
Stated interest rate		7.50%		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%			101.00%
Senior Secured Notes, 7.5% | Senior Notes | Level 2
Debt Instrument [Line Items]
Fair value of debt instrument				$ 243,500,000
Senior Convertible Notes, 2.75% | Senior Notes
Debt Instrument [Line Items]
Stated interest rate			2.75%
Face amount			$ 86,300,000
Debt instrument, redemption price, percentage of principal amount redeemed			100.00%	100.00%
Proceeds from issuance of Convertible Senior Notes			$ 83,700,000
Debt instrument, convertible, conversion ratio			0.0533547
Debt Instrument, convertible, 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				$ 75,300,000
Revolving Credit Facility | U.S revolving credit facility
Debt Instrument [Line Items]
Stated interest rate				9.25%			9.25%
Revolving credit facility				$ 23,700,000	90,000,000.0
Outstanding letters of credit issued				61,400,000
Revolving Credit Facility | Foreign line of credit
Debt Instrument [Line Items]
Credit facility face amount										$ 100,000,000		$ 80,000,000	$ 50,000,000
Revolving credit facility				0	35,000,000.0
Outstanding letters of credit issued				0
Casthouse Facility
Debt Instrument [Line Items]
Credit facility face 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				$ 104,300,000
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				8.86%			8.86%
Revolving credit facility				$ 5,500,000	0
Secured debt				98,800,000	49,400,000
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
Medium-term Notes | EURIBOR
Debt Instrument [Line Items]
Long-term debt				$ 1,300,000			€ 1.1
Iceland Term Facility | Foreign line of credit
Debt Instrument [Line Items]
Stated interest rate				3.20%			3.20%
Revolving credit facility				$ 1,300,000	13,300,000
Secured debt				$ 0	1,200,000
Vlissingen Facility Agreement | Foreign line of credit
Debt Instrument [Line Items]
Stated interest rate				8.75%			8.75%
Revolving credit facility				$ 10,000,000.0	$ 0
Secured debt				$ 10,000,000.0
Vlissingen Facility Agreement | Secured Debt | Vlissingen
Debt Instrument [Line Items]
Stated interest rate								8.75%
Face amount								$ 90,000,000

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