Business and basis of presentation.

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- Definition

Disposal group including discontinued operation working capital adjustment to cash consideration payable.

+ References

No definition available.

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- Definition

Number of manufacturing facility.

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Payment made to investment in joint venture from proceeds from sale of business.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

Amount of loss contingency liability.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
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- Definition

Dividends received on equity and other investments during the current period.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-Subparagraph (b)
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Business and Basis of Presentation (Narrative) (Details) $ in Millions			3 Months Ended	9 Months Ended	12 Months Ended
	Nov. 25, 2019 Facility	Mar. 04, 2019 Facility	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2019
Business And Basis Of Presentation [Line Items]
Amount remitted for portion of remaining proceeds				$ 25.9
EMEA and Pacific Rim Business [Member]
Business And Basis Of Presentation [Line Items]
Consideration received in connection with sale of businesses					$ 330.0
Knauf [Member]
Business And Basis Of Presentation [Line Items]
Discontinued operation, working capital adjustment to cash consideration payable				6.4
Contingent accrued liabilities			$ 0.0	$ 0.0
Knauf [Member] \| Forecast [Member]
Business And Basis Of Presentation [Line Items]
Contingent accrued liabilities						$ 11.0
WAVE [Member]
Business And Basis Of Presentation [Line Items]
Equity interest percentage			50.00%	50.00%			50.00%
Amount remitted for portion of remaining proceeds			$ 5.9	$ 25.9
Dividend received from joint venture				$ 13.0
MRK Industries, Inc. [Member]
Business And Basis Of Presentation [Line Items]
Number of manufacturing facility \| Facility	1
Architectural Components Group, Inc. [Member]
Business And Basis Of Presentation [Line Items]
Number of manufacturing facility \| Facility		1