Property and Equipment, Net - Tabular Disclosure (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Property and equipment, net
Property and equipment, gross	$ 31,820	$ 26,672
Less: Accumulated depreciation and amortization	(17,306)	(14,213)
Property and equipment, net	14,514	12,459
Computer equipment
Property and equipment, net
Property and equipment, gross	14,928	12,349
Computer software
Property and equipment, net
Property and equipment, gross	3,401	3,048
Leasehold improvements
Property and equipment, net
Property and equipment, gross	6,628	6,327
Furniture and fixtures
Property and equipment, net
Property and equipment, gross	3,333	2,870
Office equipment
Property and equipment, net
Property and equipment, gross	104	99
Construction in progress
Property and equipment, net
Property and equipment, gross	456
Internal-use software
Property and equipment, net
Property and equipment, gross	$ 2,970	$ 1,979

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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