Segment Reporting and Geographic Information - Schedule of Revenue from External Customers by Products and Services (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total revenue	$ 556,496	$ 305,896	$ 273,784
Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%
Systems and Software [Member]
Segment Reporting Information [Line Items]
Total revenue	$ 450,459	$ 255,723	$ 234,241
Systems and Software [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	80.00%	84.00%	86.00%
Parts Revenue [Member]
Segment Reporting Information [Line Items]
Total revenue	$ 65,444	$ 34,892	$ 28,658
Parts Revenue [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	12.00%	11.00%	10.00%
Service Revenue [Member]
Segment Reporting Information [Line Items]
Total revenue	$ 40,593	$ 15,281	$ 10,885
Service Revenue [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	8.00%	5.00%	4.00%