v3.7.0.1
Document And Entity Information - USD ($)
$ in Millions
12 Months Ended
Jun. 30, 2017
Sep. 01, 2017
Dec. 31, 2016
Document Information [Line Items]      
Entity Registrant Name Aviragen Therapeutics, Inc.    
Entity Central Index Key 0000072444    
Trading Symbol avir    
Current Fiscal Year End Date --06-30    
Entity Filer Category Smaller Reporting Company    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Common Stock, Shares Outstanding (in shares)   38,649,237  
Entity Public Float     $ 47.1
Document Type 10-K    
Document Period End Date Jun. 30, 2017    
Document Fiscal Year Focus 2017    
Document Fiscal Period Focus FY    
Amendment Flag false