BENEFIT PLANS:- Maximum number of shares issued to employees that could be vested (Details) - $ / shares	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
BENEFIT PLANS:
Number of Shares - Non-vested	42,667	34,750
Number of Shares - Granted	9,000	29,200
Number of Shares - Vested	(14,833)	(21,283)
Number of Shares - Forfeited	(4,000)
Number of Shares - Non-vested	32,834	42,667
Weighted Average Grant Date Fair Value Non-vested	$ 6.87	$ 6.35
Weighted Average Grant Date Fair Value Granted	6.35	7.05
Weighted Average Grant Date Fair Value Vested	6.59	6.25
Weighted Average Grant Date Fair Value Forfeited	6.76
Weighted Average Grant Date Fair Value Non-vested	$ 6.86	$ 6.87