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- Definition

Loss Contingencies, Overall Liability

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Loss Contingencies, Unpaid Service Taxes

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Loss Contingency, Amount Seeking From Other Party

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- Definition

Loss Contingency, Fine Issued By Court

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Number Of Potentially Related Parties

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- Definition

Penalties

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Proposed Civil Penalty

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- Definition

Total Environmental Liabilities

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Undiscounted amount of the accrual for environmental loss contingencies.

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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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Amount of loss contingency liability.

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Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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Number of claims dismissed.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Number of pending claims pertaining to a loss contingency.

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Commitments and Contingencies (Details) € in Thousands						3 Months Ended	9 Months Ended
Commitments and Contingencies (Details) € in Thousands	Sep. 30, 2025 USD ($) claim	Sep. 30, 2025 BRL (R$)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 BRL (R$)	Mar. 22, 2022 USD ($)	Sep. 30, 2025 USD ($) claim	Sep. 30, 2025 USD ($) case claim	Sep. 30, 2025 BRL (R$) claim	Jan. 17, 2025 company	Dec. 31, 2024 USD ($)	Jul. 19, 2024 EUR (€)	Nov. 30, 2022 USD ($)	Feb. 25, 2022 EUR (€)	Oct. 14, 2021 EUR (€)	Dec. 30, 2020 USD ($)	Jan. 27, 2020 party
Commitments and Contingencies
Number Of Potentially Related Parties									30
Reserve for loss contingencies	$ 28,800,000					$ 28,800,000	$ 28,800,000
Penalties	6,000,000					6,000,000	6,000,000	R$ 32,000,000
Current Portion of Environmental Liabilities	10,622,000					10,622,000	10,622,000			$ 11,815,000
Environmental liabilities	42,147,000					42,147,000	42,147,000			46,585,000
Total environmental liabilities	52,769,000					52,769,000	52,769,000			58,400,000
BRAZIL
Commitments and Contingencies
Loss Contingencies, Unpaid Service Taxes															$ 2,000,000
Loss Contingencies, Overall Liability	$ 6,900,000					$ 6,900,000	6,900,000
Loss Contingency Accrual, Provision							$ 0
Kentucky Department of Environmental Protection
Commitments and Contingencies
Current Portion of Environmental Liabilities										200,000
Proposed civil penalty										$ 800,000		$ 800,000
Other
Commitments and Contingencies
Number of pending claims \| claim	17,000					17,000	17,000	17,000
Number of claims dismissed to date by stipulation or summary judgment prior to trial \| case							28,500
Loss Contingency Accrual, Provision							$ 0
Alleged Violation of Environmental Permit in Ijmuiden, Netherland \| Amsterdam Public Prosecutor’s Office
Commitments and Contingencies
Loss Contingency, Amount Seeking From Other Party \| €														€ 100
Loss Contingency, Fine Issued By Court \| €											€ 25		€ 5
Unfavorable Regulatory Action
Commitments and Contingencies
Loss Contingency Accrual, Provision						$ 27,200,000
Limit and Reduce the Accumulation of Customer-Owned Slag
Commitments and Contingencies
Loss contingency, damages sought, value			$ 12,000,000	R$ 66,000,000
Limit and Reduce the Accumulation of Customer-Owned Slag \| Pending Litigation \| Volta Redonda vs. CSN and Enviri
Commitments and Contingencies
Loss contingency, damages sought, value	$ 81,000,000	R$ 431,000,000
Limit and Reduce the Accumulation of Customer-Owned Slag \| CSN
Commitments and Contingencies
Loss contingency, damages sought, value			$ 50,000,000	R$ 264,000,000
Violations of the Federal Emergency Planning and Community Right-to-Know Act \| Pending Litigation
Commitments and Contingencies
Loss contingency, damages sought, value					$ 3,000,000.0
Loss contingency reserves	$ 600,000					$ 600,000	$ 600,000