Self-Insurance	12 Months Ended
	Dec. 31, 2021
Insurance [Abstract]
Self-Insurance	Self-InsuranceWe are self-insured for medical benefits and dental benefits for all qualifying Zillow Group employees. The medical plan carries a stop-loss policy which provides protection when cumulative medical claims exceed 125% of expected claims for the plan year with a limit of $1.0 million and from individual claims during the plan year exceeding $500,000. We record estimates of the total costs of claims incurred based on an analysis of historical data and independent estimates. Our liability for self-insured claims is included within accrued compensation and benefits in our consolidated balance sheets and was $7.3 million and $4.2 million, respectively, as of December 31, 2021 and 2020.