Document and Entity Information - USD ($)	12 Months Ended
	Jun. 30, 2019	Sep. 10, 2019	Dec. 31, 2018
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2019
Entity Registrant Name	PERCEPTRON INC/MI
Entity Central Index Key	0000887226
Current Fiscal Year End Date	--06-30
Entity Filer Category	Accelerated Filer
Trading Symbol	PRCP
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 72,000,000
Entity Common Stock, Shares Outstanding		9,667,217
Entity File Number	0-20206
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Tax Identification Number	382381442
Entity Address, Address Line One	47827 Halyard Drive
Entity Address, City or Town	Plymouth
Entity Address, State or Province	Michigan
Entity Address, Postal Zip Code	48170-2461
City Area Code	734
Local Phone Number	414-6100