Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2017	Dec. 30, 2016
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 103,017	$ 90,114
Less: accumulated depreciation and amortization	(34,639)	(27,931)
Equipment and leasehold improvements, net	68,378	62,183
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	16,183	13,404
Computers, data processing and other equipment
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	9,924	9,367
Leasehold improvements
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 53,653	47,971
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful Lives	7 years
Equipment and leasehold improvements, gross	$ 3,100	3,011
Vehicles
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 2,570	2,445
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	$ 15,030	$ 11,359
Minimum \| Machinery and equipment
Property, Plant and Equipment [Line Items]
Useful Lives	5 years
Minimum \| Computers, data processing and other equipment
Property, Plant and Equipment [Line Items]
Useful Lives	3 years
Minimum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Useful Lives	7 years
Minimum \| Vehicles
Property, Plant and Equipment [Line Items]
Useful Lives	5 years
Maximum \| Machinery and equipment
Property, Plant and Equipment [Line Items]
Useful Lives	10 years
Maximum \| Computers, data processing and other equipment
Property, Plant and Equipment [Line Items]
Useful Lives	7 years
Maximum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Useful Lives	22 years
Maximum \| Vehicles
Property, Plant and Equipment [Line Items]
Useful Lives	7 years

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Publisher FASB
-Name Accounting Standards Codification
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(14))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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