Document and Entity Information - USD ($)	12 Months Ended
	Jun. 30, 2020	Oct. 27, 2020	Dec. 31, 2019
Cover [Abstract]
Document Type	10-K/A
Amendment Flag	true
Document Period End Date	Jun. 30, 2020
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2020
Entity Registrant Name	PERCEPTRON INC/MI
Entity Central Index Key	0000887226
Current Fiscal Year End Date	--06-30
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Trading Symbol	PRCP
Title of 12(b) Security	Common Stock, $0.01 par value
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Entity Current Reporting Status	Yes
Entity Public Float			$ 53,000,000
Entity Common Stock, Shares Outstanding		9,779,547
Entity File Number	0-20206
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Tax Identification Number	38-2381442
Entity Address, Address Line One	47827 Halyard Drive
Entity Address, City or Town	Plymouth
Entity Address, State or Province	MI
Entity Incorporation, State or Country Code	MI
Entity Address, Postal Zip Code	48170-2461
City Area Code	734
Local Phone Number	414-6100
Document Annual Report	true
Document Transition Report	false
Amendment Description	Our Annual Report on Form 10-K for the fiscal year ended June 30, 2020, filed with the Securities and Exchange Commission on September 28, 2020, stated that some of the information required by Part III was incorporated by reference from the definitive proxy statement for our 2020 annual meeting of shareholders (the “annual meeting), as permitted by General Instruction G(3) to Form 10-K. Since the definitive proxy statement for our annual meeting has not been filed within 120 days after the end of our 2020 fiscal year, we are amending our 2020 Form 10-K to include the information previously stated to be incorporated by reference from the definitive proxy statement.