Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2023	Apr. 30, 2022
Disaggregation of Revenue [Line Items]
Total oncology services revenue	$ 53,870	$ 49,109
Pharmacology services
Disaggregation of Revenue [Line Items]
Total oncology services revenue	50,708	46,833
Other TOS revenue
Disaggregation of Revenue [Line Items]
Total oncology services revenue	3,046	2,227
Personalized oncology services
Disaggregation of Revenue [Line Items]
Total oncology services revenue	$ 116	$ 49