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Equity-based Compensation - Narrative (Details) $ in Millions			1 Months Ended		3 Months Ended		5 Months Ended	6 Months Ended		12 Months Ended		25 Months Ended
	Jun. 03, 2022 shares	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019 USD ($) shares	Jun. 30, 2022 USD ($) shares	Jun. 30, 2021 USD ($)	May 31, 2020	Jun. 30, 2022 USD ($) shares	Jun. 30, 2021 USD ($)	Dec. 31, 2020	Dec. 31, 2019 USD ($)	Jun. 30, 2022 USD ($) shares	Jun. 03, 2020 instrument shares	May 27, 2020 shares	Mar. 31, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period								4 years
Total equity-based compensation expense \| $					$ 47.0	$ 17.1		$ 89.5	$ 35.2
Cash distributions \| $								$ 0.0	$ 15.3
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit options outstanding, weighted average remaining term								10 years
Pre-IPO Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							4 years
Pre-IPO Awards \| Tranche one
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							2 years
Award vesting percentage							50.00%
Post-IPO Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period												4 years
Post-IPO Awards \| Tranche one
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period												1 year
Award vesting percentage												25.00%
Post-IPO Awards \| Quarterly vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage												6.25%
OpCo Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units not yet vested (in shares)					0			0				0
HSKB Incentive Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Economic equivalent of Unit (in shares)								1
Amount allocated to be paid if holder of grant remains employed \| $				$ 31.3	$ 1.1			$ 1.1			$ 31.3	$ 1.1			$ 5.3
Employment period										3 years	3 years
Cash distributions \| $								1.7
2020 Omnibus Incentive Plan \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Units authorized (in shares)														18,650,000
2020 Omnibus Incentive Plan \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase to authorized plan shares based on stock outstanding, percentage		5.00%
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement maximum employee subscription rate													15.00%
Number of purchase periods permitted under the ESPP \| instrument													2
Duration of each purchase period under the ESPP			6 months
Percentage of purchase price for common stock	90.00%
Shares withheld for future ESPP purchase (in shares)													7,500,000
Shares withheld for future ESPP purchase \| $					$ 0.6			$ 0.6
Stock issued during period shares employee stock purchase plans (in shares)					0			0
Total equity-based compensation expense \| $					$ 0.1			$ 0.1
Employee Stock Purchase Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares purchased (in shares)	1,500
Employee Stock Purchase Plan \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase to authorized plan shares based on stock outstanding, percentage											1.00%
ZoomInfo OpCo and HSKB 2019 Phantom Unit Plans \| HSKB Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period to settle awards				30 days
ZoomInfo OpCo and HSKB 2019 Phantom Unit Plans \| Common Units \| HSKB Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Economic equivalent of Unit (in shares)				1