Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Mar. 31, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K/A
Amendment Flag	false
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Document Transition Report	false
Entity File Number	001-32302
Entity Registrant Name	ANTARES PHARMA, INC.
Entity Central Index Key	0001016169
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	41-1350192
Entity Address, Address Line One	100 Princeton South
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Ewing
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	08628
City Area Code	609
Local Phone Number	359-3020
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	ATRS
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 739.4
Entity Common Stock, Shares Outstanding		170,579,682
Auditor Name	KPMG LLP
Auditor Location	Minneapolis, MN
Auditor Firm ID	185