Estimated cost for non groundwater elements.

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Naval environmental recoveries, percentage of costs.

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Number of landfills AWI entered into an administrative order on consent for a removal action.

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Number of landfills listed as superfund site.

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Submission date of final report to EPA.

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- Definition

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

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Increase (decrease) in the accrual for environmental loss contingencies during the reporting period.

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Indicates line item in statement of financial position that includes accrual for environmental loss contingency.

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Amount awarded from other party in judgment or settlement of litigation.

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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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Litigation and Related Matters (Narrative) (Details) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended	60 Months Ended
	Sep. 30, 2010 Site	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) Site	Sep. 30, 2025 USD ($)	Dec. 31, 2007	Dec. 31, 2021 USD ($)	Dec. 31, 2025 USD ($)
Loss Contingencies [Line Items]
Settlement agreement amount of litigation agreement							$ 53.0
Estimated cost for non-groundwater elements				$ 8.0
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]		Liabilities, Noncurrent		Liabilities, Noncurrent				Liabilities, Noncurrent
Environmental liabilities		$ 4.5		$ 4.5				$ 4.1
Reserves for potential environmental liabilities			$ 0.1		$ 0.1
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Loss Contingencies [Line Items]
Reserves for potential environmental liabilities		0.1		$ 0.7
Macon Site [Member]
Loss Contingencies [Line Items]
Number of landfills listed as Superfund site \| Site				2
Number of landfills AWI entered into an Administrative Order on Consent for a Removal Action \| Site	1
Submission date of final report to EPA	Oct. 31, 2016
Elizabeth City [Member]
Loss Contingencies [Line Items]
Percentage of site costs Navy agreed to pay						33.33%
Other Long-Term Liabilities [Member]
Loss Contingencies [Line Items]
Environmental liabilities		4.3		$ 4.3				$ 4.1
Other Current Liability [Member]
Loss Contingencies [Line Items]
Environmental liabilities		$ 0.2		$ 0.2