Property, Plant and Equipment, net (Property, Plant and Equipment) (Details) - USD ($) $ in Thousands	Sep. 28, 2018	Dec. 29, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	$ 87,538	$ 71,253
Less: accumulated depreciation and amortization	(30,067)	(27,617)
Property, plant and equipment, net	57,471	43,636
Machinery and manufacturing equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	35,552	33,664
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	10,192	9,919
Internal-use computer software
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	12,770	7,819
Building and land
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	17,803	8,811
Information systems, office equipment and furniture
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	7,329	7,715
Transportation equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment gross	$ 3,892	$ 3,325