Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Mar. 19, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Entity Filer Category	Smaller Reporting Company
Entity Registrant Name	ELECTRO SENSORS INC
Entity Central Index Key	0000351789
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Common Stock, Shares Outstanding		3,395,521
Entity Public Float			$ 5,300,000
Trading Symbol	ELSE