v3.21.1
Cover Page - USD ($)
 12 Months Ended
Jan. 31, 2021
Mar. 26, 2021
Jul. 31, 2020
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Jan. 31, 2021    
Current Fiscal Year End Date --01-31    
Document Transition Report false    
Entity File Number 001-38977    
Entity Registrant Name PHREESIA, INC.    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 20-2275479    
Entity Address, Address Line One 434 Fayetteville St    
Entity Address, Address Line Two Suite 1400    
Entity Address, City or Town Raleigh    
Entity Address, State or Province NC    
Entity Address, Postal Zip Code 27601    
City Area Code 888    
Local Phone Number 654-7473    
Title of 12(b) Security Common stock, $0.01 par value per share    
Trading Symbol PHR    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 1,138,758,080
Entity Common Stock, Shares Outstanding (in shares)   44,900,069  
Documents Incorporated by Reference
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the registrant’s Definitive Proxy Statement relating to its 2021 Annual Meeting of Stockholders to be filed hereafter are incorporated by reference into Part III of this Annual Report on Form 10-K where indicated.
    
Amendment Flag false    
Entity Central Index Key 0001412408    
Document Fiscal Year Focus 2021    
Document Fiscal Period Focus FY