Acquisitions (Narrative) (Details) $ in Thousands					3 Months Ended	12 Months Ended
	Dec. 11, 2020 USD ($)	Oct. 15, 2020 USD ($)	Feb. 13, 2020 USD ($)	Jan. 15, 2020 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) business	Jun. 30, 2021 USD ($)
Business Acquisition [Line Items]
Number of businesses acquired | business						5
Goodwill						$ 514,279	$ 508,857
Renewables
Business Acquisition [Line Items]
Number of businesses acquired | business						2
Goodwill						$ 192,527	186,944
Agtech
Business Acquisition [Line Items]
Number of businesses acquired | business						2
Goodwill						$ 84,622	84,783
Residential
Business Acquisition [Line Items]
Number of businesses acquired | business						1
Goodwill						$ 205,452	$ 205,452
TerraSmart LLC
Business Acquisition [Line Items]
Acquisition purchase price					$ 223,900
Goodwill						$ 139,106
Sunfig Corporation
Business Acquisition [Line Items]
Acquisition purchase price	$ 3,800
Goodwill	$ 3,200
Architectural Mailboxes, LLC
Business Acquisition [Line Items]
Acquisition purchase price		$ 26,900
Goodwill		$ 7,400
Delta Separations, LLC
Business Acquisition [Line Items]
Acquisition purchase price			$ 47,100
Goodwill			$ 32,200
Thermo Energy Systems
Business Acquisition [Line Items]
Acquisition purchase price				$ 7,300
Goodwill				$ 18,700