Earnings Per Share - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($)	3 Months Ended
	Jul. 31, 2019	Jul. 31, 2018
Earnings Per Share [Abstract]
Net income	$ 866,000	$ 617,000
Basic EPS	$ 866,000	$ 617,000
Basic EPS, shares	4,956,389	4,967,580
Basic EPS, per share	$ 0.17	$ 0.12
Effect of dilutive Convertible Preferred Stock
Effect of dilutive Convertible Preferred Stock, shares	20,500	20,500
Effect of dilutive Convertible Preferred Stock, per share	$ (.0007)	$ (.0005)
Diluted EPS	$ 866,000	$ 617,000
Diluted EPS, shares	4,976,889	4,988,080
Diluted EPS, per share	$ 0.17	$ 0.12