Property and Equipment, Net - Components of Property and Equipment, Net (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 109.5	$ 101.6
Less: Accumulated depreciation	(72.9)	(71.3)
Total property and equipment, net	36.6	30.3
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	36.1	34.1
Software [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	36.6	36.4
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	8.5	8.0
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 28.3	$ 23.1

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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