| Cover | Jun. 27, 2024 |
| Entity Addresses [Line Items] | |
| Document Type | 8-K12B |
| Amendment Flag | false |
| Document Period End Date | Jun. 27, 2024 |
| Current Fiscal Year End Date | --12-31 |
| Entity File Number | 001-38492 |
| Entity Registrant Name | Kiniksa Pharmaceuticals International, plc |
| Entity Central Index Key | 0001730430 |
| Entity Tax Identification Number | 00-0000000 |
| Entity Incorporation, State or Country Code | X0 |
| Entity Address, Address Line One | Third Floor, 23 Old Bond Street |
| Entity Address, City or Town | London |
| Entity Address, Country | GB |
| Entity Address, Postal Zip Code | W1S 4PZ |
| City Area Code | 808 |
| Local Phone Number | 451-3453 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Class A Ordinary Shares $0.000273235 nominal value |
| Trading Symbol | KNSA |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Information, Former Legal or Registered Name | Kiniksa Pharmaceuticals, Ltd. |
| Former Address [Member] | |
| Entity Addresses [Line Items] | |
| Entity Address, Address Line One | 100 Hayden Avenue |
| Entity Address, City or Town | Lexington |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02421 |
