Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Property and Equipment
Property and equipment, gross	$ 100,579	$ 79,190
Accumulated depreciation and amortization	(39,284)	(31,102)
Total property and equipment, net	61,295	48,088
Depreciation expense	9,200	8,600	$ 7,400
Computer, office equipment and software
Property and Equipment
Property and equipment, gross	30,627	27,082
Leasehold improvements
Property and Equipment
Property and equipment, gross	55,471	40,782
Furniture
Property and Equipment
Property and equipment, gross	$ 14,481	$ 11,326

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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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.

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