Note L - Stockholders' Equity - Schedule of Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Balance	$ 123,369	$ 115,432	$ 102,715	$ 79,686	$ 115,432	$ 79,686
Net earnings	3,513	7,690	2,471	11,184	11,203	13,655
Other comprehensive income (loss)		317	1,579	7,174
Paid in capital – restricted stock units	78	78	73	73
Cash dividends	(148)	(148)	(148)	(157)
Repurchase of shares	(3)			(29)
Balance	126,809	123,369	106,690	102,715	126,809	106,690
Plateplus Inc. [Member]
Shares issued - Plateplus business combination				4,784		4,800
Common Stock [Member]
Balance	8,869	8,869	8,861	8,345	8,869	8,345
Net earnings	0	0	0	0
Other comprehensive income (loss)		0	0	0
Paid in capital – restricted stock units	0	0	0	0
Cash dividends	0	0	0	0
Repurchase of shares	0			0
Balance	8,869	8,869	8,861	8,861	8,869	8,861
Common Stock [Member] | Plateplus Inc. [Member]
Shares issued - Plateplus business combination				516
AOCI Attributable to Parent [Member]
Balance	0	(317)	(3,095)	(10,269)	(317)	(10,269)
Net earnings	0	0	0	0
Other comprehensive income (loss)		317	1,579	7,174
Paid in capital – restricted stock units	0	0	0	0
Cash dividends	0	0	0	0
Repurchase of shares	0			0
Balance	0	0	(1,516)	(3,095)	0	(1,516)
AOCI Attributable to Parent [Member] | Plateplus Inc. [Member]
Shares issued - Plateplus business combination				0
Additional Paid-in Capital [Member]
Balance	35,083	35,005	34,783	30,442	35,005	30,442
Net earnings	0	0	0	0
Other comprehensive income (loss)		0	0	0
Paid in capital – restricted stock units	78	78	73	73
Cash dividends	0	0	0	0
Repurchase of shares	0			0
Balance	35,161	35,083	34,856	34,783	35,161	34,856
Additional Paid-in Capital [Member] | Plateplus Inc. [Member]
Shares issued - Plateplus business combination				4,268
Treasury Stock, Common [Member]
Balance	(7,778)	(7,778)	(7,770)	(7,741)	(7,778)	(7,741)
Net earnings	0	0	0	0
Other comprehensive income (loss)		0	0	0
Paid in capital – restricted stock units	0	0	0	0
Cash dividends	0	0	0	0
Repurchase of shares	(3)			(29)
Shares issued - Plateplus business combination				0
Balance	(7,781)	(7,778)	(7,770)	(7,770)	(7,781)	(7,770)
Retained Earnings [Member]
Balance	87,195	79,653	69,936	58,909	79,653	58,909
Net earnings	3,513	7,690	2,471	11,184
Other comprehensive income (loss)		0	0	0
Paid in capital – restricted stock units	0	0	0	0
Cash dividends	(148)	(148)	(148)	(157)
Repurchase of shares	0			0
Balance	$ 90,560	$ 87,195	$ 72,259	69,936	$ 90,560	$ 72,259
Retained Earnings [Member] | Plateplus Inc. [Member]
Shares issued - Plateplus business combination				$ 0