XML 14 R1.htm IDEA: XBRL DOCUMENT v3.10.0.1
Document and Entity Information - USD ($)
$ in Millions
 12 Months Ended
Sep. 30, 2018
Nov. 30, 2018
Mar. 31, 2018
Document and Entity Information      
Entity Registrant Name INNOVATIVE SOLUTIONS & SUPPORT INC    
Entity Central Index Key 0000836690    
Document Type 10-K    
Document Period End Date Sep. 30, 2018    
Amendment Flag false    
Current Fiscal Year End Date --09-30    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Filer Category Non-accelerated Filer    
Entity Public Float     $ 44.7
Entity Common Stock, Shares Outstanding   16,840,599  
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY