Document and Entity Information (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Dec. 02, 2011	Mar. 31, 2011
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, 2011
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	Accelerated Filer
Entity Public Float			$ 74.6
Entity Common Stock, Shares Outstanding		16,719,806
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	FY