Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2025	Mar. 06, 2026	Jun. 30, 2025
Document Information [Line Items]
Document Type	10-K/A
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Document Transition Report	false
Entity File Number	001-35285
Entity Registrant Name	Vaxart, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	59-1212264
Entity Address, Address Line One	310 Utah Avenue, Suite 150
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	650
Local Phone Number	550-3500
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	VXRT
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	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 102,712,906
Entity Common Stock, Shares Outstanding (in shares)		240,634,372
Amendment Description	Vaxart, Inc. (the “Company,” “we,” “us,” or “our”) previously filed its Annual Report on Form 10-K for the year ended December 31, 2025 (the “Original Form 10-K”) with the Securities and Exchange Commission (the “SEC”) on March 13, 2026. In accordance with General Instruction G(3) of Form 10-K, this Amendment No. 1 to the Original Form 10-K (this “Amendment”) is being filed solely for the purpose of filing the information required by Part III of Form 10-K.
Entity Central Index Key	0000072444
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Amendment Flag	true