Document And Entity Information - USD ($)	12 Months Ended
	Sep. 30, 2016	Nov. 08, 2016	Mar. 31, 2016
Document And Entity Information [Abstract]
Entity Registrant Name	DATAWATCH CORP
Entity Central Index Key	0000792130
Current Fiscal Year End Date	--09-30
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		11,923,786
Entity Public Float			$ 46,637,207
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2016
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2016