Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2025	Jan. 31, 2024	Jan. 31, 2025	Jan. 31, 2024
Disaggregation of Revenue [Line Items]
Total oncology revenue	$ 17,039	$ 12,019	$ 44,589	$ 36,153
Pharmacology services
Disaggregation of Revenue [Line Items]
Total oncology revenue	11,670	11,184	37,237	33,919
TOS license revenue
Disaggregation of Revenue [Line Items]
Total oncology revenue	4,500	0	4,500	0
Other TOS revenue
Disaggregation of Revenue [Line Items]
Total oncology revenue	869	835	2,852	2,216
Personalized oncology services
Disaggregation of Revenue [Line Items]
Total oncology revenue	$ 0	$ 0	$ 0	$ 18