Condensed Statements of Stockholders' Equity (Unaudited) - USD ($)	Preferred Stock [Member]	Common Stock Class A [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Beginning balance, value at Apr. 30, 2020	$ 99,000	$ 850,000	$ 1,934,000	$ (4,301,000)	$ (4,000)	$ 41,006,000	$ 39,584,000
Beginning balance, shares at Apr. 30, 2020	4,100	8,502,881		3,552,954
Purchases of common stock				$ (28,000)			(28,000)
Purchases of common stock, shares				2,825
Dividend declared at $0.42 per common share outstanding						(2,079,000)	(2,079,000)
Unrealized (loss), net of tax effect					133,000		133,000
Net Income						7,799,000	7,799,000
Ending balance, value at Jan. 31, 2021	$ 99,000	$ 850,000	1,934,000	$ (4,329,000)	129,000	46,726,000	45,409,000
Ending balance, shares at Jan. 31, 2021	4,100	8,502,881		3,555,779
Beginning balance, value at Oct. 31, 2020	$ 99,000	$ 850,000	1,934,000	$ (4,302,000)	87,000	42,279,000	40,947,000
Beginning balance, shares at Oct. 31, 2020	4,100	8,502,881		3,553,029
Purchases of common stock				$ (27,000)			(27,000)
Purchases of common stock, shares				2,750
Unrealized (loss), net of tax effect					42,000		42,000
Net Income						4,447,000	4,447,000
Ending balance, value at Jan. 31, 2021	$ 99,000	$ 850,000	1,934,000	$ (4,329,000)	129,000	46,726,000	45,409,000
Ending balance, shares at Jan. 31, 2021	4,100	8,502,881		3,555,779
Beginning balance, value at Apr. 30, 2021	$ 99,000	$ 850,000	1,934,000	$ (4,336,000)	108,000	49,749,000	48,404,000
Beginning balance, shares at Apr. 30, 2021	4,100	8,502,881		3,556,412
Purchases of common stock				$ (35,000)			(35,000)
Purchases of common stock, shares				2,713
Dividend declared at $0.42 per common share outstanding						(2,472,000)	(2,472,000)
Unrealized (loss), net of tax effect					(103,000)		(103,000)
Net Income						3,595,000	3,595,000
Ending balance, value at Jan. 31, 2022	$ 99,000	$ 850,000	1,934,000	$ (4,371,000)	5,000	50,872,000	49,389,000
Ending balance, shares at Jan. 31, 2022	4,100	8,502,881		3,559,125
Beginning balance, value at Oct. 31, 2021	$ 99,000	$ 850,000	1,934,000	$ (4,362,000)	72,000	50,711,000	49,304,000
Beginning balance, shares at Oct. 31, 2021	4,100	8,502,881		3,558,425
Purchases of common stock				$ (9,000)			(9,000)
Purchases of common stock, shares				700
Unrealized (loss), net of tax effect					(67,000)		(67,000)
Net Income						161,000	161,000
Ending balance, value at Jan. 31, 2022	$ 99,000	$ 850,000	$ 1,934,000	$ (4,371,000)	$ 5,000	$ 50,872,000	$ 49,389,000
Ending balance, shares at Jan. 31, 2022	4,100	8,502,881		3,559,125