| Cover | Nov. 03, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 3, 2021 |
| Entity File Number | 001-33957 |
| Entity Registrant Name | HARVARD BIOSCIENCE, INC. |
| Entity Central Index Key | 0001123494 |
| Entity Tax Identification Number | 04-3306140 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 84 October Hill Road |
| Entity Address, City or Town | Holliston |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 01746 |
| City Area Code | (508) |
| Local Phone Number | 893-8999 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | HBIO |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
