v3.3.1.900
Document And Entity Information - USD ($)
$ in Millions
12 Months Ended
Dec. 26, 2015
Feb. 11, 2016
Jun. 26, 2015
Entity Registrant Name COHU INC    
Entity Central Index Key 0000021535    
Trading Symbol cohu    
Current Fiscal Year End Date --12-26    
Entity Filer Category Accelerated Filer    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Common Stock, Shares Outstanding (in shares)   26,249,438  
Entity Public Float     $ 193
Document Type 10-K    
Document Period End Date Dec. 26, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus FY    
Amendment Flag false