Commitments and Contingencies	6 Months Ended
Oct. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	(15) Commitments and Contingencies Employment Litigation On August 28, 2018, counsel for Charles Dunleavy, the Company’s former President & Chief Executive Officer who was terminated for cause effective June 9, 2014, filed a demand for arbitration, captioned Charles F. Dunleavy v. Ocean Power Technologies, Inc., Case No. 01-18-0003-2374, before the American Arbitration Association in New Jersey. The demand alleged various claims relating to Mr. Dunleavy’s termination. After the hearings in the proceeding were conducted, on December 11, 2020, the arbitration panel issued an interim award finding, among other things, that the termination for cause of Mr. Dunleavy was in breach of his employment contract and awarded him compensatory damages in the amount of $438,254.54. On May 3, 2021, the panel issued a second interim award and therein awarded Mr. Dunleavy attorneys’ fees, costs and pre-judgment interest. The Company agreed, on May 24, 2021, to pay Mr. Dunleavy $1,223,963.14, representing the total compensatory damages, attorneys’ fees, costs and pre-judgment interest, which is the full amount awarded by the arbitration panel. The Company made the required payment on May 26, 2021, and the matter is now closed. Spain Income Tax Audit The Company underwent an income tax audit in Spain for the period from 2011 to 2014, when our Spanish branch was closed. On July 30, 2018, the Spanish tax inspector concluded that although there was no tax owed in light of losses reported, the Company’s Spanish branch owed penalties for failure to properly account for the income associated with the funding grant. During the six months ended October 31, 2020, the Company received notice from the Spanish Central Economic and Administrative Tribunal that it agreed with the inspector and ruled that the Company owes the full amount of the penalty in the amount of €279,870 or approximately $331,000. On January 25, 2021, the Company paid to the Spanish Tax Administration €279,870. Notwithstanding that payment, on April 30, 2021, the Company filed its appeal of the decision of the Central Court to the Spanish National Court. There is no schedule for a ruling from the Spanish National Court.

Commitments and Contingencies

6 Months Ended

Oct. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

(15) Commitments and Contingencies

Employment Litigation

On August 28, 2018, counsel for Charles Dunleavy, the Company’s former President & Chief Executive Officer who was terminated for cause effective June 9, 2014, filed a demand for arbitration, captioned Charles F. Dunleavy v. Ocean Power Technologies, Inc., Case No. 01-18-0003-2374, before the American Arbitration Association in New Jersey. The demand alleged various claims relating to Mr. Dunleavy’s termination. After the hearings in the proceeding were conducted, on December 11, 2020, the arbitration panel issued an interim award finding, among other things, that the termination for cause of Mr. Dunleavy was in breach of his employment contract and awarded him compensatory damages in the amount of $438,254.54. On May 3, 2021, the panel issued a second interim award and therein awarded Mr. Dunleavy attorneys’ fees, costs and pre-judgment interest. The Company agreed, on May 24, 2021, to pay Mr. Dunleavy $1,223,963.14, representing the total compensatory damages, attorneys’ fees, costs and pre-judgment interest, which is the full amount awarded by the arbitration panel. The Company made the required payment on May 26, 2021, and the matter is now closed.

Spain Income Tax Audit

The Company underwent an income tax audit in Spain for the period from 2011 to 2014, when our Spanish branch was closed. On July 30, 2018, the Spanish tax inspector concluded that although there was no tax owed in light of losses reported, the Company’s Spanish branch owed penalties for failure to properly account for the income associated with the funding grant. During the six months ended October 31, 2020, the Company received notice from the Spanish Central Economic and Administrative Tribunal that it agreed with the inspector and ruled that the Company owes the full amount of the penalty in the amount of €279,870 or approximately $331,000. On January 25, 2021, the Company paid to the Spanish Tax Administration €279,870. Notwithstanding that payment, on April 30, 2021, the Company filed its appeal of the decision of the Central Court to the Spanish National Court. There is no schedule for a ruling from the Spanish National Court.