XML 43 R1.htm IDEA: XBRL DOCUMENT v3.19.3
Document and Entity Information - shares
 3 Months Ended
Sep. 30, 2019
Nov. 07, 2019
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Sep. 30, 2019  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q1  
Trading Symbol IIVI  
Entity Registrant Name II-VI INC  
Entity Central Index Key 0000820318  
Entity Current Reporting Status Yes  
Current Fiscal Year End Date --06-30  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Common Stock, Shares Outstanding   90,849,196
Entity Shell Company false  
Entity File Number 0-16195  
Entity Tax Identification Number 25-1214948  
Entity Address, Address Line One 375 Saxonburg Boulevard  
Entity Address, City or Town Saxonburg  
Entity Address, State or Province PA  
Entity Address, Postal Zip Code 16056  
City Area Code 724  
Entity Interactive Data Current Yes  
Local Phone Number 352-4455  
Title of 12(b) Security Common Stock, no par value  
Security Exchange Name NASDAQ  
Entity Incorporation, State or Country Code PA  
Document Quarterly Report true  
Document Transition Report false