| Document and Entity Information | Feb. 09, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Feb. 9, 2022 |
| Entity Registrant Name | APTEVO THERAPEUTICS INC. |
| Entity Central Index Key | 0001671584 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-37746 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 81-1567056 |
| Entity Address, Address Line One | 2401 4th Avenue |
| Entity Address, Address Line Two | Suite 1050 |
| Entity Address, City or Town | Seattle |
| Entity Address, State or Province | WA |
| Entity Address, Postal Zip Code | 98121 |
| City Area Code | 206 |
| Local Phone Number | 838-0500 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.001 par value |
| Trading Symbol | APVO |
| Security Exchange Name | NASDAQ |
