Schedule I - Condensed Financial Information of Registrant - Notes to Condensed Financial Statements (Details) $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|---|
Mar. 29, 2021 |
Sep. 30, 2021
USD ($)
|
Sep. 30, 2020
USD ($)
|
Sep. 30, 2021
USD ($)
|
Sep. 30, 2020
USD ($)
|
Dec. 31, 2020
USD ($)
|
Dec. 31, 2019
USD ($)
|
Dec. 31, 2018
USD ($)
|
Aug. 18, 2017 |
|
| Stock split, conversion ratio | 0.333 | ||||||||
| Income tax expense (benefit) | $ 3,270 | $ (1,376) | $ 8,361 | $ 1,975 | $ (3,144) | $ 12,053 | $ (1,197) | ||
| DoubleVerify Inc. | |||||||||
| Ownership percentage acquired | 100.00% | ||||||||
| Parent Company | Reportable Legal Entities | |||||||||
| Stock split, conversion ratio | 0.333 | ||||||||
| Income tax expense (benefit) | (3,144) | 12,053 | (1,197) | ||||||
| Distributions from subsidiaries | $ 0 | $ 0 | $ 0 | ||||||
| Parent Company | Reportable Legal Entities | DoubleVerify Inc. | |||||||||
| Ownership percentage acquired | 100.00% | ||||||||
| X | ||||||||||
- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount after tax of income (loss) of subsidiary attributable to the parent entity. No definition available.
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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| X | ||||||||||
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| X | ||||||||||
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