Document and Entity Information
6 Months Ended
Jun. 30, 2015
Jul. 28, 2015
Document and Entity Information [Abstract]    
Entity Registrant Name RUBICON PROJECT, INC.  
Entity Central Index Key 0001595974  
Document Type 10-Q  
Document Period End Date Jun. 30, 2015  
Amendment Flag false  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q2  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Entity Common Stock, Shares Outstanding   43,835,507