Property and equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Machinery, equipment and software	$ 13,007	$ 6,733
Leasehold improvements	9,549	8,673
Furniture and fixtures	3,027	2,827
Store fixtures	13,481	10,896
Property and equipment, gross	39,064	29,129
Less: Accumulated depreciation and amortization	(17,260)	(11,092)
Property and equipment, net	$ 21,804	$ 18,037

Machinery equipment and software, gross.

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- Definition

Store fixtures gross.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

+ References

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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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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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