Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Property and equipment	$ 662	$ 643
Less: accumulated amortization and depreciation	(289)	(283)
Property and equipment, net	373	360
Website development costs
Property, Plant and Equipment [Line Items]
Property and equipment	597	564
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	32	45
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment	17	18
Office equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	12	16
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment	$ 4	$ 0

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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