Debt Instrument, Term Extension

No definition available.

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- Definition

Debt Instrument, Variable Interest Rate

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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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

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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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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Related Party Transactions - Narrative (Details) - USD ($)		3 Months Ended		6 Months Ended
	Oct. 01, 2024	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Related Party Transaction [Line Items]
Net sales		$ 752,100,000	$ 628,100,000	$ 1,401,300,000	$ 1,262,000,000
Glencore \| Supply Commitment
Related Party Transaction [Line Items]
Net sales		$ 50,200,000	$ 48,000,000.0	$ 111,500,000	$ 126,400,000
Glencore \| Consolidated sales \| Customer concentration risk
Related Party Transaction [Line Items]
Major customer, percentage of revenue, net (percent)		44.00%	58.50%	45.50%	59.10%
Vlissingen \| Vlissingen Credit Facility \| Affiliated Entity
Related Party Transaction [Line Items]
Term extension	2 years
Credit facility face amount	$ 90,000,000.0
Debt instrument, basis spread on variable rate	3.687%
Secured debt		$ 0		$ 0
Vlissingen \| Vlissingen Credit Facility \| Affiliated Entity \| Maximum
Related Party Transaction [Line Items]
Variable interest rate	9.00%
Vlissingen \| Vlissingen Credit Facility \| Affiliated Entity \| Minimum
Related Party Transaction [Line Items]
Variable interest rate	7.00%
Century Aluminum \| Glencore
Related Party Transaction [Line Items]
Glencore beneficial ownership		30.00%		30.00%