v3.19.2
Document and Entity Information - USD ($)
12 Months Ended
Apr. 30, 2019
Jul. 01, 2019
Oct. 31, 2018
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Apr. 30, 2019    
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Trading Symbol KALV    
Entity Registrant Name KALVISTA PHARMACEUTICALS, INC.    
Entity Central Index Key 0001348911    
Current Fiscal Year End Date --04-30    
Entity Well-known Seasoned Issuer No    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Accelerated Filer    
Entity Shell Company false    
Entity Small Business false    
Entity Emerging Growth Company true    
Entity Ex Transition Period true    
Entity Common Stock, Shares Outstanding   17,388,298  
Entity Public Float     $ 177,929,193