v3.20.2

Income Tax Provision - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2020 USD ($) segment | Jun. 30, 2019 USD ($) | Jun. 30, 2020 USD ($) segment | Jun. 30, 2019 USD ($) | Dec. 31, 2019 USD ($) agreement | Dec. 31, 2018 USD ($) | Jun. 08, 2020 USD ($)
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Number of subsidiaries, corporations | segment | 2 |  | 2 |  |  |  |
Income tax benefit | $ 12.9 | $ 1.4 | $ 13.3 | $ 4.7 |  |  |
Effective income tax rate | 17.60% |  |  |  |  |  |
Deferred tax asset position from outside differences in partnership subsidiaries |  |  |  |  |  |  | $ 211.9
Tax benefits realized which must be paid (as a percent) |  |  | 85.00% |  |  |  |
Expected benefit from remaining cash savings (as a percent) |  |  | 15.00% |  |  |  |
Projected obligations under Tax Receivable Agreements | $ 109.4 |  | $ 109.4 |  |  |  |
Outside basis differences in partnership subsidiaries |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Valuation allowance |  |  |  |  |  |  | 276.0
Outside basis in corporate stock of wholly owned subsidiary |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Valuation allowance |  |  |  |  |  |  | $ 119.0
DiscoverOrg Holdings |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Number of subsidiaries, corporations | agreement |  |  |  |  | 2 |  |
Income tax benefit |  |  |  |  | $ 6.5 | $ 2.9 |
Effective income tax rate |  |  |  |  | 7.70% | 9.10% |
Valuation allowance |  |  |  |  | $ 2.2 | $ 0.0 |
DiscoverOrg Holdings | Foreign Tax Authority |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
NOL carryforward |  |  |  |  | 13.5 |  |
DiscoverOrg Holdings | Foreign Tax Authority | Research Tax Credit Carryforward [Member] |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Federal and state research and development credit carryforwards | 0.4 |  | 0.4 |  |  |  |
DiscoverOrg Holdings | State and Local Jurisdiction |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
NOL carryforward |  |  |  |  | $ 34.6 |  |
DiscoverOrg Holdings | State and Local Jurisdiction | Research Tax Credit Carryforward [Member] |  |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Federal and state research and development credit carryforwards | $ 1.1 |  | $ 1.1 |  |  |  |

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the entity's investment in its wholly-owned subsidiaries. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 + Details
Name: | us-gaap_DeferredTaxAssetsInvestmentInSubsidiaries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
Name: | us-gaap_DeferredTaxAssetsValuationAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_EffectiveIncomeTaxRateContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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_IncomeTaxContingencyLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I.7) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32672-109319 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120385591&loc=d3e38679-109324 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(9)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
Name: | us-gaap_OperatingLossCarryforwards
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
Name: | us-gaap_TaxCreditCarryforwardAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of Subsidiaries, C Corporations + References No definition available. + Details
Name: | zi_NumberOfSubsidiariesCCorporations
Namespace Prefix: | zi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Tax Receivable Agreement, Cash Savings Realized, Percentage + References No definition available. + Details
Name: | zi_TaxReceivableAgreementCashSavingsRealizedPercentage
Namespace Prefix: | zi_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tax Receivable Agreement, Projected Obligation + References No definition available. + Details
Name: | zi_TaxReceivableAgreementProjectedObligation
Namespace Prefix: | zi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Tax Receivable Agreement, Tax Benefits Realized Which Must Then Be Paid, Percentage + References No definition available. + Details
Name: | zi_TaxReceivableAgreementTaxBenefitsRealizedWhichMustThenBePaidPercentage
Namespace Prefix: | zi_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ValuationAllowanceByDeferredTaxAssetAxis=zi_ValuationAllowanceForDeferredTaxAssetRelatedToOutsideBasisInPartnershipSubsidiariesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationAllowanceByDeferredTaxAssetAxis=zi_ValuationAllowanceForDeferredTaxAssetRelatedToOutsideBasisInWhollyOwnedSubsidiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=zi_DiscoverOrgHoldingsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_ForeignCountryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TaxCreditCarryforwardAxis=us-gaap_ResearchMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |