v3.7.0.1
Document and Entity Information - shares
3 Months Ended
Apr. 30, 2017
Jun. 06, 2017
Document And Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Apr. 30, 2017  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q1  
Trading Symbol COUP  
Entity Registrant Name Coupa Software Incorporated  
Entity Central Index Key 0001385867  
Current Fiscal Year End Date --01-31  
Entity Filer Category Non-accelerated Filer  
Entity Common Stock, Shares Outstanding   52,987,247