Leases - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2024	Oct. 31, 2023
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 454	$ 454	$ 907	$ 907
Weighted average remaining lease term (in years)	4 years 2 months 26 days	5 years 2 months 19 days	4 years 2 months 26 days	5 years 2 months 19 days
Weighted average discount rate, percent	5.88%	5.87%	5.88%	5.87%
Corporate Headquarters
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 19	$ 19	$ 38	$ 38
Rockville, MD
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	422	423	843	846
Milan Italy
Lessee, Lease, Description [Line Items]
Operating leases, rent expense	$ 13	$ 13	$ 25	$ 26