| Cover | Jun. 29, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jun. 29, 2022 |
| Entity Registrant Name | Exicure, Inc. |
| Entity Central Index Key | 0001698530 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-39011 |
| Entity Tax Identification Number | 81-5333008 |
| Entity Address, Address Line One | 2430 N. Halsted St. |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60614 |
| City Area Code | 847 |
| Local Phone Number | 673-1700 |
| 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 $0.0001 per share |
| Trading Symbol | XCUR |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | true |
| Current Fiscal Year End Date | --12-31 |
