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	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net income	$ 155	$ 228	$ 293	$ 95
Shares outstanding - basic (in shares)	6,054	5,965	6,042	5,942
Earnings per share - basic (in dollars per share)	$ 0.03	$ 0.04	$ 0.05	$ 0.02
Effective dilutive securities – common stock options and restricted stock units (in shares)	109	8	105	21
Net income - diluted	$ 155	$ 228	$ 293	$ 95
Shares outstanding - diluted (in shares)	6,163	5,973	6,147	5,963
Earnings per share - diluted (in dollars per share)	$ 0.03	$ 0.04	$ 0.05	$ 0.02
Net income	$ 155	$ 228	$ 293	$ 95
Diluted income per share	$ 155	$ 228	$ 293	$ 95