Note L - Stockholders' Equity - Schedule of Stockholders' Equity (Details) - USD ($)		3 Months Ended				6 Months Ended
	Apr. 30, 2022	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Balance		$ 102,715,030	$ 79,686,648	$ 62,942,275	$ 65,339,976	$ 79,686,648	$ 65,339,976
Net earnings		2,470,908	11,184,374	13,177,614	11,311,797	13,655,282	24,489,411
Other comprehensive income (loss)		1,578,033	7,174,117	4,227,185	(13,693,337)
Paid in capital – restricted stock awards		73,153	73,153	126,037	121,704
Repurchase of shares			(29,268)
Cash dividends		(147,372)	(157,694)	(138,110)	(137,865)
Issuance of restricted stock				0
Balance		106,689,752	102,715,030	80,335,001	62,942,275	106,689,752	80,335,001
Plateplus Inc. [Member]
Shares issued – Plateplus business combination	$ 4,800,000		4,783,700			4,783,700
Common Stock [Member]
Balance		8,861,016	8,344,975	8,334,785	8,334,785	8,344,975	8,334,785
Net earnings		0	0	0	0
Other comprehensive income (loss)		0	0	0	0
Paid in capital – restricted stock awards		0	0	0	0
Repurchase of shares			0
Cash dividends		0	0	0	0
Issuance of restricted stock				6,000
Balance		8,861,016	8,861,016	8,340,785	8,334,785	8,861,016	8,340,785
Common Stock [Member] | Plateplus Inc. [Member]
Shares issued – Plateplus business combination			516,041
AOCI Attributable to Parent [Member]
Balance		(3,094,392)	(10,268,509)	(24,881,178)	(11,187,841)	(10,268,509)	(11,187,841)
Net earnings		0	0	0	0
Other comprehensive income (loss)		1,578,033	7,174,117	4,227,185	(13,693,337)
Paid in capital – restricted stock awards		0	0	0	0
Repurchase of shares			0
Cash dividends		0	0	0	0
Issuance of restricted stock				0
Balance		(1,516,359)	(3,094,392)	(20,653,993)	(24,881,178)	(1,516,359)	(20,653,993)
AOCI Attributable to Parent [Member] | Plateplus Inc. [Member]
Shares issued – Plateplus business combination			0
Additional Paid-in Capital [Member]
Balance		34,783,173	30,442,361	30,125,166	30,003,462	30,442,361	30,003,462
Net earnings		0	0	0	0
Other comprehensive income (loss)		0	0	0	0
Paid in capital – restricted stock awards		73,153	73,153	126,037	121,704
Repurchase of shares			0
Cash dividends		0	0	0	0
Issuance of restricted stock				(6,000)
Balance		34,856,326	34,783,173	30,245,203	30,125,166	34,856,326	30,245,203
Additional Paid-in Capital [Member] | Plateplus Inc. [Member]
Shares issued – Plateplus business combination			4,267,659
Treasury Stock [Member]
Balance		(7,770,465)	(7,741,197)	(7,203,342)	(7,203,342)	(7,741,197)	(7,203,342)
Net earnings		0	0	0	0
Other comprehensive income (loss)		0	0	0	0
Paid in capital – restricted stock awards		0	0	0	0
Repurchase of shares			(29,268)
Cash dividends		0	0	0	0
Issuance of restricted stock				0
Balance		(7,770,465)	(7,770,465)	(7,203,342)	(7,203,342)	(7,770,465)	(7,203,342)
Treasury Stock [Member] | Plateplus Inc. [Member]
Shares issued – Plateplus business combination			0
Retained Earnings [Member]
Balance		69,935,698	58,909,018	56,566,844	45,392,912	58,909,018	45,392,912
Net earnings		2,470,908	11,184,374	13,177,614	11,311,797
Other comprehensive income (loss)		0	0	0	0
Paid in capital – restricted stock awards		0	0	0	0
Repurchase of shares			0
Cash dividends		(147,372)	(157,694)	(138,110)	(137,865)
Issuance of restricted stock				0
Balance		$ 72,259,234	69,935,698	$ 69,606,348	$ 56,566,844	$ 72,259,234	$ 69,606,348
Retained Earnings [Member] | Plateplus Inc. [Member]
Shares issued – Plateplus business combination			$ 0