Summary of Significant Accounting Policies - Other Long-Term Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 2.2	$ 1.7
Website development and internal-use software costs	$ 5.7	$ 2.8
Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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