Document and Entity Information - USD ($)	12 Months Ended
	Jun. 30, 2018	Aug. 21, 2018	Dec. 31, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jun. 30, 2018
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2018
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			$ 84,000,000
Entity Common Stock, Shares Outstanding		9,555,767