Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Mar. 24, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Trading Symbol	APVO
Entity Registrant Name	APTEVO THERAPEUTICS INC.
Entity Central Index Key	0001671584
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Common Stock, Shares Outstanding		5,007,241
Entity Public Float			$ 93.1
Title of 12(b) Security	Common Stock, $0.001 par value per share
Security Exchange Name	NASDAQ
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
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	Portions of the Registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission pursuant to Regulation 14A, not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K, relating to the Registrant’s 2022 Annual Meeting of Stockholders are incorporated by reference into Part III of this Report.
Auditor Name	Moss Adams LLP
Auditor Firm ID	659
Auditor Location	Seattle, WA