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Acquisitions (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands			12 Months Ended
	Aug. 30, 2019	Aug. 21, 2018	Dec. 31, 2020
TerraSmart LLC
Business Acquisition [Line Items]
Fair Value			$ 51,700
TerraSmart LLC \| Trademarks
Business Acquisition [Line Items]
Fair Value			16,400
TerraSmart LLC \| Trademarks
Business Acquisition [Line Items]
Fair Value			$ 300
Weighted-Average Amortization Period			7 years
TerraSmart LLC \| Technology
Business Acquisition [Line Items]
Fair Value			$ 2,500
Weighted-Average Amortization Period			15 years
TerraSmart LLC \| Customer relationships
Business Acquisition [Line Items]
Fair Value			$ 24,000
Weighted-Average Amortization Period			10 years
TerraSmart LLC \| Non-compete agreements
Business Acquisition [Line Items]
Fair Value			$ 2,200
Weighted-Average Amortization Period			5 years
TerraSmart LLC \| Backlog
Business Acquisition [Line Items]
Fair Value			$ 6,300
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc.
Business Acquisition [Line Items]
Fair Value			38,296
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Trademarks
Business Acquisition [Line Items]
Fair Value			8,200
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Trademarks
Business Acquisition [Line Items]
Fair Value			$ 1,177
Weighted-Average Amortization Period			3 years
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Technology
Business Acquisition [Line Items]
Fair Value			$ 8,175
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Technology \| Minimum
Business Acquisition [Line Items]
Weighted-Average Amortization Period			7 years
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Technology \| Maximum
Business Acquisition [Line Items]
Weighted-Average Amortization Period			15 years
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Customer relationships
Business Acquisition [Line Items]
Fair Value			$ 18,780
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Customer relationships \| Minimum
Business Acquisition [Line Items]
Weighted-Average Amortization Period			5 years
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Customer relationships \| Maximum
Business Acquisition [Line Items]
Weighted-Average Amortization Period			13 years
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Non-compete agreements
Business Acquisition [Line Items]
Fair Value			$ 1,036
Weighted-Average Amortization Period			5 years
Sunfig Corporation, Architectural Mailboxes, LLC, Delta Separations, LLC, and Thermo Energy Systems Inc. \| Backlog
Business Acquisition [Line Items]
Fair Value			$ 928
Weighted-Average Amortization Period			1 year
Apeks
Business Acquisition [Line Items]
Fair Value	$ 3,000
Apeks \| Trademarks
Business Acquisition [Line Items]
Fair Value	1,400
Apeks \| Technology
Business Acquisition [Line Items]
Fair Value	$ 900
Weighted-Average Amortization Period	7 years
Apeks \| Customer relationships
Business Acquisition [Line Items]
Fair Value	$ 700
Weighted-Average Amortization Period	6 years
SolarBOS
Business Acquisition [Line Items]
Fair Value		$ 1,450
SolarBOS \| Trademarks
Business Acquisition [Line Items]
Fair Value		$ 300
Weighted-Average Amortization Period		3 years
SolarBOS \| Technology
Business Acquisition [Line Items]
Fair Value		$ 450
Weighted-Average Amortization Period		9 years
SolarBOS \| Customer relationships
Business Acquisition [Line Items]
Fair Value		$ 700
Weighted-Average Amortization Period		9 years