Identified Intangible Assets and Goodwill, Net Schedule of Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Dec. 31, 2019
Goodwill [Line Items]
Goodwill	$ 42,285	$ 37,971	$ 37,971
Goodwill, acquisitions	2,576	1,798	4,174
Goodwill, translation and other adjustments	291	129
Goodwill	45,152	39,898	42,285
Remaining three months of 2020	700
Finite-Lived Intangible Assets, Amortization Expense, Year Two	2,475
Finite-Lived Intangible Assets, Amortization Expense, Year Three	2,244
Finite-Lived Intangible Assets, Amortization Expense, Year Four	2,076
Finite-Lived Intangible Assets, Amortization Expense, Year Five	1,601
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	1,750
Intangible assets, net	10,846		10,934
Utility [Member]
Goodwill [Line Items]
Goodwill	4,911	4,911	4,911
Goodwill, acquisitions	0	0
Goodwill, translation and other adjustments	0	0
Goodwill	4,911	4,911	4,911
Residential commercial [Member]
Goodwill [Line Items]
Goodwill	37,374	33,060	33,060
Goodwill, acquisitions	2,576	1,798
Goodwill, translation and other adjustments	291	129
Goodwill	$ 40,241	$ 34,987	$ 37,374