Long-Lived Assets - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment	$ 315,351	$ 224,417
Less accumulated depreciation and amortization	(145,413)	(98,610)
Property and equipment, net	169,938	125,807
Depreciation and amortization	49,600	32,600	$ 24,200
Content
Property, Plant and Equipment [Line Items]
Property and equipment	258,005	181,938
Internal-use software and website development
Property, Plant and Equipment [Line Items]
Property and equipment	29,711	15,646
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	19,913	19,574
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	4,352	3,891
Computers and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	$ 3,370	$ 3,368

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 aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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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