Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property and Equipment, Net
Property and equipment, gross	$ 81,942	$ 67,100
Accumulated depreciation and amortization	(24,299)	(14,801)
Property and equipment, net	57,643	52,299
Depreciation expense	11,600	8,900	$ 5,500
Computer hardware
Property and Equipment, Net
Property and equipment, gross	8,685	5,114
Furniture and office equipment
Property and Equipment, Net
Property and equipment, gross	18,478	14,888
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	50,461	45,158
Leasehold improvements in process
Property and Equipment, Net
Property and equipment, gross	$ 4,318	$ 1,940

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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