Note 12 - Earnings Per Share - Summary of Reconciliations Between the Numerator and the Denominator of the Basic and Diluted Earnings Per Share Computations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Net income	$ 2,154	$ 920	$ 387
Shares outstanding - basic (in shares)	6,157	6,070	5,956
Earnings per share - basic (in dollars per share)	$ 0.35	$ 0.15	$ 0.06
Effective dilutive securities—Common stock options and restricted stock units	$ 0	$ 0	$ 0
Effective dilutive securities—Common stock options and restricted stock units (in shares)	11	8	4
Net income - diluted	$ 2,154	$ 920	$ 387
Shares outstanding - diluted (in shares)	6,168	6,079	5,959
Diluted income per share (in dollars per share)	$ 0.35	$ 0.15	$ 0.06
Diluted (in dollars per share)	0.35	0.15	0.06
Basic (in dollars per share)	$ 0.35	$ 0.15	$ 0.06