Restructuring Costs	12 Months Ended
	Apr. 30, 2021
Restructuring and Related Activities [Abstract]
Restructuring Costs	Restructuring CostsIn December 2019, the Company initiated a restructuring, which included the addition of a new Vice President of Information Technology to lead the transformation and modernization of the Company's information systems, and a reduction in workforce primarily in its domestic operations to reduce operating expenses on an ongoing basis. This restructuring plan, which included the closure of the Company's subsidiary in China, a commercial sales organization for the Company's products in China, was substantially completed as of April 30, 2020. In fiscal year 2021, the Company incurred severance expenses in its international operations related to the closure of the China subsidiary of $25,000. The Company reflected all the expenses as operating expenses in the Consolidated Statement of Operations. The Company now expects the remaining administrative requirements for closure of the China subsidiary to be completed by the end of fiscal year 2022.