Income Taxes (Details) - Schedule of Deferred Tax Assets and Liabilities - USD ($) $ in Thousands	Apr. 30, 2022	Apr. 30, 2021
Deferred tax assets:
Employee benefits	$ 3,047	$ 4,789
Inventory	2,958	1,946
Accounts receivable	118	119
Tax credits	2,306	2,027
Other assets	981	883
Lease Liability	2,284	2,593
Capital Loss carry-forward	2,513	2,602
Net operating loss carryforwards	7,574	6,203
Total deferred tax asset	21,781	21,162
Deferred tax liabilities:
Property, plant and equipment	(461)	(666)
Right of use asset	(2,211)	(2,514)
Other liabilities	(83)	(195)
Deferred state income tax	(943)	(932)
Net deferred tax asset	18,083	16,855
Valuation allowance	(18,091)	(16,863)
Net deferred tax (liability) asset	$ (8)	$ (8)