| Document And Entity Information | Jul. 25, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jul. 25, 2023 |
| Entity Registrant Name | Larimar Therapeutics, Inc. |
| Entity Central Index Key | 0001374690 |
| Entity Emerging Growth Company | false |
| Securities Act File Number | 001-36510 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 20-3857670 |
| Entity Address, Address Line One | Three Bala Plaza East |
| Entity Address, City or Town | Bala Cynwyd |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19004 |
| City Area Code | (844) |
| Local Phone Number | 511-9056 |
| 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 $0.001 per share |
| Trading Symbol | lrmr |
| Security Exchange Name | NASDAQ |
