XML 14 R1.htm IDEA: XBRL DOCUMENT v3.22.2
Cover - USD ($)
$ in Millions
 12 Months Ended
Apr. 30, 2022
Jul. 13, 2022
Oct. 31, 2021
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Apr. 30, 2022    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2022    
Current Fiscal Year End Date --04-30    
Entity File Number 001-33417    
Entity Registrant Name Ocean Power Technologies, Inc.    
Entity Central Index Key 0001378140    
Entity Tax Identification Number 22-2535818    
Entity Incorporation, State or Country Code DE    
Entity Address, Address Line One 28 ENGELHARD DRIVE    
Entity Address, Address Line Two SUITE B    
Entity Address, City or Town MONROE TOWNSHIP    
Entity Address, State or Province NJ    
Entity Address, Postal Zip Code 08831    
City Area Code (609)    
Local Phone Number 730-0400    
Title of 12(b) Security Common Stock, par value $0.001    
Trading Symbol OPTT    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Public Float     $ 40.8
Entity Common Stock, Shares Outstanding   55,881,861  
ICFR Auditor Attestation Flag true    
Auditor Firm ID 274    
Auditor Name EisnerAmper LLP    
Auditor Location Iselin, New Jersey