The number of locations under collective bargaining arrangements.

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- Definition

The number of locations under collective bargaining arrangements expiring during the year.

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- Definition

The number of satellite recycled aluminum slab centers in aluminum operations.

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No definition available.

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- Definition

The percentage of employees covered by a collective bargaining agreement as of the balance sheet date.

+ References

No definition available.

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The percentage of employees covered by a collective bargaining agreement expiring during the year.

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No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

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Description of the Business and Summary of Significant Accounting Policies - Description of the Business (Details) $ in Thousands		12 Months Ended
	Apr. 01, 2023	Dec. 31, 2024 USD ($) state item segment	Dec. 31, 2023 USD ($)
Segment Reporting Information
Number of reportable segments \| segment		4
Workforce represented by collective bargaining agreements (as a percent)		5.00%
Number of locations under collective bargaining arrangements \| state		4
Percentage of workforce subject to collective bargaining arrangements expiring during the year		0.50%
Number of locations subject to collective bargaining agreements expiring \| state		1
Redeemable noncontrolling interests		$ 171,212	$ 171,212
United Steel Supply, LLC
Segment Reporting Information
Noncontrolling interest, ownership percentage	90.00%	90.00%	90.00%
Redeemable noncontrolling interests		$ 60,000	$ 60,000
United Steel Supply, LLC \| Steel Operations
Segment Reporting Information
Noncontrolling interest, ownership percentage	90.00%
SDI Biocarbon Solutions
Segment Reporting Information
Noncontrolling interest, ownership percentage		75.00%
Mesabi Nugget
Segment Reporting Information
Noncontrolling interest, ownership percentage		86.00%	86.00%
Redeemable noncontrolling interests		$ 111,200	$ 111,200
Unity Aluminum, Inc \| Aluminum Operations
Segment Reporting Information
Number Of Satellite Recycled Aluminum Slab Centers \| item		2
Noncontrolling interest, ownership percentage		94.40%