Document and Entity Information Document
9 Months Ended
Sep. 30, 2012
Oct. 19, 2012
Document And Entity Information [Abstract]    
Entity Registrant Name VERISIGN INC/CA  
Entity Central Index Key 0001014473  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Document Type 10-Q  
Document Period End Date Sep. 30, 2012  
Document Fiscal Year Focus 2012  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   155,256,629