Equipment, Leasehold Improvements and Software - Summary of Equipment, Leasehold Improvements and Software (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 28, 2019	Dec. 28, 2018
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 147,543	$ 136,776
Less: accumulated depreciation and amortization	(57,345)	(51,500)
Equipment, leasehold improvements and software, net	90,198	85,276
Land
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 1,170	1,170
Buildings
Property, Plant and Equipment [Line Items]
Useful lives	20 years
Equipment and leasehold improvements, gross	$ 1,292	1,292
Machinery and equipment
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 19,539	17,837
Machinery and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Useful lives	5 years
Machinery and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Useful lives	10 years
Computers, data processing and other equipment
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 12,615	11,244
Computers, data processing and other equipment \| Minimum
Property, Plant and Equipment [Line Items]
Useful lives	3 years
Computers, data processing and other equipment \| Maximum
Property, Plant and Equipment [Line Items]
Useful lives	7 years
Software
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 22,963	22,779
Software \| Minimum
Property, Plant and Equipment [Line Items]
Useful lives	3 years
Software \| Maximum
Property, Plant and Equipment [Line Items]
Useful lives	7 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 64,919	60,565
Leasehold improvements \| Minimum
Property, Plant and Equipment [Line Items]
Useful lives	1 year
Leasehold improvements \| Maximum
Property, Plant and Equipment [Line Items]
Useful lives	40 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful lives	7 years
Equipment and leasehold improvements, gross	$ 3,364	3,268
Vehicles
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 4,164	2,769
Vehicles \| Minimum
Property, Plant and Equipment [Line Items]
Useful lives	5 years
Vehicles \| Maximum
Property, Plant and Equipment [Line Items]
Useful lives	7 years
Other
Property, Plant and Equipment [Line Items]
Useful lives	7 years
Equipment and leasehold improvements, gross	$ 95	95
Construction-in-process
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 17,422	$ 15,757

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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