Summary of Significant Accounting Policies (Details - Revenue) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020
Product Information [Line Items]
Revenues	$ 30,754	$ 25,392
Manufacturing Revenue [Member]
Product Information [Line Items]
Revenues	25,675	24,063
Process Development Revenue [Member]
Product Information [Line Items]
Revenues	$ 5,079	$ 1,329