Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Aggregate cash proceeds received from a combination of transactions that are classified as investing activities in which assets, which may include one or more investments, are sold to third-party buyers. This element can be used by entities to aggregate proceeds from all asset sales that are classified as investing activities.

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Indicates title and position of individual or name of group identified as chief operating decision maker (CODM) for segment reporting.

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Nature of Operations (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2024
Segment Reporting Information [Line Items]
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]			President and Chief Executive Officer [Member]
Architectural Specialties [Member]
Segment Reporting Information [Line Items]
Proceeds from the sale of assets			$ 2.1
Gain on sale of properties	$ 0.0
WAVE [Member]
Segment Reporting Information [Line Items]
Equity interest percentage	50.00%		50.00%
Plant in St.Helens, Oregon [Member]
Segment Reporting Information [Line Items]
Proceeds from the sale of assets			$ 9.4
Gain on sale of properties			4.6
Land in Lancaster, Pennsylvania [Member]
Segment Reporting Information [Line Items]
Proceeds from the sale of assets			$ 12.8
Gain on sale of properties	$ 0.3
Asset impairment loss		$ 4.9