Balance Sheet Information - Property and equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 121,752	$ 108,276
Accumulated depreciation and amortization	(52,683)	(48,239)
Property and equipment, net	69,069	60,037
Computer and networking equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	101,593	89,830
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,278	3,285
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	679	681
Office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	616	579
Internal-use software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	15,586	13,901
Property and equipment, net	$ 9,600	$ 8,500

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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