Property and Equipment, net (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 49,322	$ 45,333
Accumulated depreciation	(21,563)	(19,600)
Property and equipment, net	27,759	25,733
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,497	4,198
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,522	10,704
Survey and field equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	27,586	24,165
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 6,717	$ 6,266

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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