Debt Instrument, Principal Payment

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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest Payable Outstanding

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

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Balance Type:	debit
Period Type:	instant

- Definition

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

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Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

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Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

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Balance Type:	debit
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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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount for notes payable (written promise to pay), due to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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.

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Balance Type:	credit
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.

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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.

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- Details

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- Details

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- Details

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Debt - Activity (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020	Jul. 01, 2020
Debt Instrument [Line Items]
Hawesville term loan - current portion	$ 15,000,000.0	$ 20,000,000.0
Hancock County industrial revenue bonds (IRBs) due April 1, 2028, interest payable quarterly (variable interest rates (not to exceed 12%))	7,800,000	7,800,000
Total debt	316,600,000	315,900,000
Long-term Debt [Member] \| Revolving credit facility [Member] \| Iceland revolving line of credit [Member]
Debt Instrument [Line Items]
Revolving credit facility	0	45,000,000.0
Long-term Debt [Member] \| Senior Secured Notes Due June 01, 2025 [Member]
Debt Instrument [Line Items]
Senior securities notes	$ 243,400,000	243,100,000
Stated interest rate, percentage	12.00%		12.00%
Debt discount	$ 2,200,000	2,300,000
Financing fees	4,400,000	4,600,000
Short-term Debt [Member] \| Industrial revenue bonds due April 1, 2028 [Member]
Debt Instrument [Line Items]
Hancock County industrial revenue bonds (IRBs) due April 1, 2028, interest payable quarterly (variable interest rates (not to exceed 12%))	$ 7,800,000	7,800,000
Stated interest rate, percentage	0.20%
Short-term Debt [Member] \| Industrial revenue bonds due April 1, 2028 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Effective interest rate, maximum	12.00%
Short-term Debt [Member] \| Revolving credit facility [Member]
Debt Instrument [Line Items]
Stated interest rate, percentage	5.375%
Interest payable outstanding	$ 0
Principal payment	25,000,000.0
Interest payable	$ 2,200,000
Short-term Debt [Member] \| Revolving credit facility [Member] \| Revolving Credit Facility, Portion Subject To LIBOR Rate [Member]
Debt Instrument [Line Items]
Stated interest rate, percentage	0.20%
Short-term Debt [Member] \| Revolving credit facility [Member] \| U.S. revolving credit facility [Member]
Debt Instrument [Line Items]
Revolving credit facility	$ 50,400,000	0
Stated interest rate, percentage	3.80%
Hawesville [Member] \| Short-term Debt [Member]
Debt Instrument [Line Items]
Hawesville term loan - current portion	$ 15,000,000.0	$ 20,000,000.0