Property and Equipment, net - Detail of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment	$ 345,490	$ 305,927
Less: accumulated amortization and depreciation	(175,001)	(170,755)
Property and equipment, net	170,489	135,172
Website development costs
Property, Plant and Equipment [Line Items]
Property and equipment	149,648	149,891
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	81,981	65,012
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment	45,337	29,037
Office equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	36,582	39,510
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment	$ 31,942	$ 22,477

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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