Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Oct. 02, 2020	Dec. 31, 2019	Sep. 27, 2019	Dec. 31, 2018
Other Liabilities Disclosure [Abstract]
Accrued compensation and benefits	$ 10,964	$ 15,359
Accrued warranty	5,102	5,756	$ 4,728	$ 4,510
Contract liabilities, current portion	4,540	3,219
Deferred purchase price for acquisitions	23,463	27,735
Finance lease obligations	9,503	1,307
Accrued earn-out and contingent considerations	11,626	3,813
Other	11,038	13,137
Total	$ 76,236	$ 70,326