| Document And Entity Information | May 27, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | May 27, 2022 |
| Entity Registrant Name | CVENT HOLDING CORP. |
| Entity Central Index Key | 0001827075 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-39709 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 98-1560055 |
| Entity Address, Address Line One | 1765 Greensboro Station Place |
| Entity Address, Address Line Two | 7th Floor |
| Entity Address, City or Town | Tysons |
| Entity Address, State or Province | VA |
| Entity Address, Postal Zip Code | 22102 |
| City Area Code | 703 |
| Local Phone Number | 226-3500 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, par value $0.0001 per share |
| Trading Symbol | CVT |
| Security Exchange Name | NASDAQ |
