| Document And Entity Information | Sep. 26, 2021 |
| Document Information [Line Items] | |
| Entity, Registrant Name | DIAMEDICA THERAPEUTICS INC. |
| Document, Type | 8-K |
| Document, Period End Date | Sep. 26, 2021 |
| Entity, Incorporation, State or Country Code | A1 |
| Entity, File Number | 001-36291 |
| Entity, Address, Address Line One | Two Carlson Parkway, Suite 260 |
| Entity, Address, City or Town | Minneapolis |
| Entity, Address, State or Province | MN |
| Entity, Address, Postal Zip Code | 55447 |
| City Area Code | 763 |
| Local Phone Number | 312-6755 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Voting common shares |
| Trading Symbol | DMAC |
| Security Exchange Name | NASDAQ |
| Entity, Emerging Growth Company | true |
| Entity, Ex Transition Period | true |
| Amendment Flag | false |
| Entity, Central Index Key | 0001401040 |
