Share-Based Awards - Additional Information (Detail) $ / shares in Units, $ in Millions				3 Months Ended	12 Months Ended
	Aug. 03, 2022 USD ($) employee $ / shares shares	Jun. 09, 2020 shares	Aug. 08, 2019 shares	Mar. 31, 2023	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares) | shares		12,000,000
Vesting period				3 years	4 years
Zillow Group, Inc. 2020 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares of common and capital stock available for issuance, percentage		5.00%
Exercise price per share fixed		100.00%
2019 Equity Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares) | shares			10,000,000
Exercise price per share fixed			100.00%
Option awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, fair value assumptions, exercise price (USD per share) | $ / shares	$ 38.78
Share-based payment arrangement, plan modification, number of awards impacted | shares	7,000,000
Share-based payment arrangement, plan modification, number of grantees affected | employee	3,348
Share-based payment arrangement, plan modification, expected incremental cost	$ 66
Unrecognized cost of unvested share-based compensation awards					$ 335
Unrecognized compensation cost expected recognition period					2 years 3 months 18 days
Total intrinsic value of shares					$ 20	$ 13	$ 310
Fair value of options					$ 215	226	173
Option awards | Zillow Group, Inc. 2020 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment, award maximum exercisable period					12 months
Expiration period					10 years
Vesting period					4 years
Option awards | 2019 Equity Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment, award maximum exercisable period					12 months
Expiration period					10 years
Share based compensation arrangement by share based payment, award minimum exercisable period					3 months
Option awards | 2019 Equity Inducement Plan | Vesting, Option Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					4 years
Unvested restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost expected recognition period					2 years 4 months 24 days
Total fair value of awards vested					$ 292	$ 247	$ 152
Total unrecognized compensation cost					$ 494
Unvested restricted stock units | Zillow Group, Inc. 2020 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					4 years
Unvested restricted stock units | 2019 Equity Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					4 years
Share-Based Payment Arrangement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, plan modification, grants in period, weighted average grant date fair value (USD per share) | $ / shares	$ 67.58