Leases - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2023	Jul. 31, 2022
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 453	$ 467
Weighted average remaining lease term (in years)	5 years 5 months 19 days
Weighted average discount rate, percent	5.87%
Corporate Headquarters
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 19	21
Rockville, MD
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	423	422
Milan Italy
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 13	$ 23