Debt Instrument, Variable Interest Rate, Maximum Percentage

No definition available.

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- Definition

Carrying value as of the balance sheet date of the long-term debt associated with industrial revenue bonds. For classified balance sheets, these bonds are considered current assets because they are remarketed weekly and the bonds could be required to be repaid upon demand if there is a failed remarketing.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

+ References

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- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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+ Details

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Period Type:	instant

- Definition

Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

+ Details

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Period Type:	instant

- Details

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Debt - Activity (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Apr. 30, 2021
Debt Instrument [Line Items]
Hancock County industrial revenue bonds ("IRBs") due April 1, 2028, interest payable quarterly	$ 7.8	$ 7.8
Grundartangi casthouse debt facility	69.3	49.4
Convertible senior notes	84.5	84.4
Total debt	553.4	527.7
Industrial revenue bonds, variable
Debt Instrument [Line Items]
Hancock County industrial revenue bonds ("IRBs") due April 1, 2028, interest payable quarterly	$ 7.8	7.8
Maximum variable interest rate	12.00%
Effective interest rate	4.14%
Revolving credit facility \| U.S. revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility	$ 63.2	90.0
Effective interest rate	9.00%
Revolving credit facility \| Iceland revolving line of credit
Debt Instrument [Line Items]
Revolving credit facility	$ 73.0	35.0
Effective interest rate	8.16%
Casthouse Facility \| Iceland revolving line of credit
Debt Instrument [Line Items]
Secured debt	$ 69.3	49.4
Financing fees	$ 0.7
Effective interest rate	8.63%
Iceland term facility \| Iceland revolving line of credit
Debt Instrument [Line Items]
Revolving credit facility	$ 8.6	13.3
Secured debt	0.0	1.2
Financing fees	$ 0.0
Stated interest rate, percentage	3.20%
Effective interest rate	6.46%
Senior secured notes, 7.5% \| Senior notes
Debt Instrument [Line Items]
Grundartangi casthouse debt facility	$ 247.0	246.6
Financing fees	$ 3.0
Stated interest rate, percentage	7.50%		7.50%
Senior convertible notes, 2.75% \| Senior notes
Debt Instrument [Line Items]
Convertible senior notes	$ 84.5	$ 84.4
Financing fees	$ 1.7
Stated interest rate, percentage	2.75%