Document And Entity Information - shares	3 Months Ended
	Sep. 30, 2015	Oct. 29, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	LSI Industries Inc.
Trading Symbol	lyts
Document Type	10-Q
Current Fiscal Year End Date	--06-30
Entity Common Stock, Shares Outstanding		24,562,726
Amendment Flag	false
Entity Central Index Key	0000763532
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Well-known Seasoned Issuer	No
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q1