Acquisitions (Narrative) (Details) - USD ($) $ in Millions	Aug. 24, 2020	Jul. 27, 2020	Nov. 25, 2019	Mar. 04, 2019	Sep. 30, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Business acquisition, liabilities, contingent consideration					$ 15.9
Business acquisition, goodwill					$ 108.2	$ 53.0
Moz Designs, Inc.
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 4.2
Business acquisition, liabilities, contingent consideration	2.5
Business acquisition, total fair value of liabilities assumed, less tangible assets acquired	0.5
Business acquisition, total fair value of intangible assets acquired	3.2
Business acquisition, goodwill	4.0
Moz Designs, Inc. | Maximum [Member]
Business Acquisition [Line Items]
Business acquisition, liabilities, contingent consideration	4.7
Moz Designs, Inc. | TradeNames [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired	1.7
Moz Designs, Inc. | Customer Relationships [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired	$ 1.5
Turf [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price		$ 70.0
Business acquisition, liabilities, contingent consideration		13.4
Business acquisition, total fair value of intangible assets acquired		27.9
Business acquisition, goodwill		50.7
Business acquisition, total fair value of tangible assets acquired, less liabilities assumed		4.8
Turf [Member] | Target Payout [Member]
Business Acquisition [Line Items]
Additional cash considerations		$ 24.0
Annual growth rate of contingent consideration		23.00%
Turf [Member] | Over Target Payout [Member]
Business Acquisition [Line Items]
Annual growth rate of contingent consideration		38.00%
Turf [Member] | Patents [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired		$ 5.8
Turf [Member] | Non-compete Agreements [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired		3.3
Turf [Member] | Maximum [Member]
Business Acquisition [Line Items]
Business combination additional contingent consideration payable		48.0
Turf [Member] | Maximum [Member] | Over Target Payout [Member]
Business Acquisition [Line Items]
Additional cash considerations		24.0
Turf [Member] | TradeNames [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired		9.6
Turf [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired		$ 7.7
MRK Industries, Inc. [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price			$ 13.3
Business acquisition, goodwill			10.4
Business acquisition, total fair value of tangible assets acquired, less liabilities assumed			$ 2.9
Architectural Components Group, Inc. [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price				$ 42.9
Business acquisition, total fair value of intangible assets acquired				12.0
Business acquisition, goodwill				23.6
Business acquisition, total fair value of tangible assets acquired, less liabilities assumed				7.3
Architectural Components Group, Inc. [Member] | TradeNames [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired				2.8
Architectural Components Group, Inc. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Business acquisition, total fair value of intangible assets acquired				$ 7.4