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 current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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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Property and Equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,080,389	$ 897,141
Less accumulated depreciation and amortization	(455,845)	(290,164)
Property and equipment, net	624,544	606,977		$ 379,268
Depreciation and amortization	191,600	122,600	$ 85,900
Furniture and computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	509,120	339,761
Site and software development costs
Property, Plant and Equipment [Line Items]
Property and equipment, gross	297,252	172,653
Property and equipment, net	123,500	62,900
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	228,514	109,929
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	45,503	90,104
Building
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 0	$ 184,694