Employee Benefit Plan - Additional Information (Detail) - Zillow Merger - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Contribution Plan Disclosure [Line Items]
Company's contribution based on employee contribution (up to)	4.00%
Company's expense related to its defined contribution 401(k) retirement plans	$ 32.3	$ 25.6	$ 20.8