| Document And Entity Information | Aug. 15, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Current Fiscal Year End Date | --12-31 |
| Document Period End Date | Aug. 15, 2024 |
| Entity Registrant Name | KLDiscovery Inc. |
| Entity Central Index Key | 0001752474 |
| Entity Emerging Growth Company | true |
| Entity File Number | 001-38789 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 61-1898603 |
| Entity Address, Address Line One | 9023 Columbine Road |
| Entity Address, City or Town | Eden Prairie |
| Entity Address, State or Province | MN |
| Entity Address, Postal Zip Code | 55347 |
| City Area Code | 888 |
| Local Phone Number | 811-3789 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Ex Transition Period | false |
| Title of 12(b) Security | N/A |
| No Trading Symbol Flag | true |
| Security Exchange Name | NONE |
| Amendment Description | This amendment to the Current Report on Form 8-K is being filed to include the Introductory Note to the Report, which was inadvertently omitted from the original Form 8-K filed on August 15, 2024 (the “Original 8-K”). Except as set forth herein, the Company has not updated any information contained therein to reflect any events that have occurred since the date of the Original 8-K. |
