Note 6 - Debt - Schedule of Debt Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2025	Apr. 30, 2024
Note Collateralized by Single Aircraft Due November 2029
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	7.19%	7.19%
Debt instrument, periodic payment terms, balloon payment to be paid	$ 2,500	$ 2,500
Note Collateralized by Real Estate Due March 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.75%	1.75%
Debt instrument, periodic payment terms, balloon payment to be paid	$ 624	$ 624
Note Collateralized by Aircraft Security Agreement
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.35%	4.35%
Debt instrument, periodic payment terms, balloon payment to be paid	$ 460	$ 460
Note Collateralized by Equipment Due April 2027
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	8.13%	8.13%
Debt instrument, periodic payment terms, balloon payment to be paid	$ 20	$ 20
Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 2,000	$ 2,000
Interest rate	8.40%	8.40%
Notes Collateralized by BHCMC's Assets and Compensation Due under State Management Contract Due December 2027
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	5.32%	5.32%
Debt instrument, periodic payment terms, balloon payment to be paid	$ 19,250	$ 19,250
Note Collateralized By All Of BHCMC's Assets and Compensation due under the State Management Contract Due October 2026
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	5.75%	5.75%