XML 83 R71.htm IDEA: XBRL DOCUMENT
v3.20.2

Commitments and Contingencies - Additional Information (Detail) | Jun. 20, 2017 USD ($) | Feb. 09, 2017 USD ($) | Sep. 30, 2020 USD ($) | Dec. 31, 2019 USD ($) | Feb. 28, 2018 claim | Feb. 05, 2018 claim | Sep. 30, 2017 claim
--- | --- | --- | --- | --- | --- | --- | ---
Other Commitments [Line Items] |  |  |  |  |  |  |
Outstanding letters of credit |  |  | $ 16,900,000 |  |  |  |
Outstanding surety bonds |  |  | 10,100,000 | $ 10,200,000 |  |  |
VHT Vs Zillow Group Inc. |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |
Jury awarded damages | $ 4,100,000 |  |  |  |  |  |
VHT Vs Zillow Group Inc. | Actual Damages |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |
Jury awarded damages |  | $ 79,875 |  |  |  |  |
VHT Vs Zillow Group Inc. | Statutory Damages |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |
Jury awarded damages |  | $ 8,200,000 |  |  |  |  |
Class Action Lawsuits |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |
Number of pending claims | claim |  |  |  |  |  |  | 2
Shareholder Derivative Lawsuits |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |
Number of pending claims | claim |  |  |  |  | 4 | 2 |
Homes under contract to purchase that have not closed |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |
Value of homes under contract that have not closed |  |  | $ 182,600,000 |  |  |  |

X
- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
Name: | us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of damages awarded to the plaintiff in the legal matter. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
Name: | us-gaap_LossContingencyDamagesAwardedValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_OtherCommitmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(17)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(19)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(25)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Surety bonds amount outstanding. + References No definition available. + Details
Name: | z_SuretyBondsAmountOutstanding
Namespace Prefix: | z_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | srt_LitigationCaseAxis=z_VHTVsZillowGroupIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=z_ActualDamagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=z_StatutoryDamagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=z_ClassActionLawsuitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=z_ShareholderDerivativeLawsuitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis=z_RealEstateUnderContractToPurchaseThatHaveNotClosedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |