Document And Entity Information - USD ($)	12 Months Ended
	Sep. 29, 2018	May 31, 2019	Mar. 31, 2018
Document Information [Line Items]
Entity Registrant Name	TECHNICAL COMMUNICATIONS CORP
Entity Central Index Key	0000096699
Trading Symbol	tcco
Current Fiscal Year End Date	--09-29
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Common Stock, Shares Outstanding (in shares)		1,850,403
Entity Public Float			$ 7,721,285
Entity Shell Company	false
Document Type	10-K
Document Period End Date	Sep. 29, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false