Document and Entity Information
| Document and Entity Information | Aug. 05, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Aug. 5, 2020 |
| Entity Registrant Name | Calyxt, Inc. |
| Entity Central Index Key | 0001705843 |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Entity File Number | 001-38161 |
| Entity Incorporation State Country Code | DE |
| Entity Tax Identification Number | 27-1967997 |
| Entity Address Address Line1 | 2800 Mount Ridge Road |
| Entity Address City Or Town | Roseville |
| Entity Address State Or Province | MN |
| Entity Address Postal Zip Code | 55113-1127 |
| City Area Code | 651 |
| Local Phone Number | 683-2807 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security12b Title | Common Stock, par value $0.0001 per share |
| Trading Symbol | CLXT |
| Security Exchange Name | NASDAQ |