Property and Equipment, net - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Amortization and depreciation expense related to property and equipment other than website development costs	$ 31.1	$ 34.1	$ 24.9
Capitalization of website development costs	85.6	54.8	42.3
Technology and development
Property, Plant and Equipment [Line Items]
Amortization of website development costs and intangible assets included in technology and development	61.3	50.5	44.9
Technology and development \| Software Development
Property, Plant and Equipment [Line Items]
Amortization of website development costs and intangible assets included in technology and development	$ 36.9	$ 24.8	$ 17.0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Additions made to capitalized computer software costs during the period.

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Amount of expense charged against earnings to allocate the cost of tangible and intangible assets over their remaining economic lives, classified as other.

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