v3.19.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2019
Apr. 20, 2019
Document And Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2019  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q1  
Trading Symbol CY  
Entity Registrant Name CYPRESS SEMICONDUCTOR CORP /DE/  
Entity Central Index Key 0000791915  
Current Fiscal Year End Date --12-29  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   365,289,260
Entity Emerging Growth Company false  
Entity Small Business false