Note 17 - Stockholders' Equity - Option Activity (Details) - $ / shares	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Outstanding, options (in shares)	2,416,667
Number of options granted (in shares)	25,000	43,000
Weighted-average exercise price per share (in dollars per share)	$ 1.75	$ 1.1
Outstanding, options (in shares)	2,266,667	2,416,667
Share-Based Payment Arrangement, Employee [Member]
Outstanding, options (in shares)	2,416,667	3,565,191
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 3.75	$ 3.78
Number of options granted (in shares)	25,000	43,000
Weighted-average exercise price per share (in dollars per share)	$ 1.75	$ 1.1
Forfeited or expired, options (in shares)	(165,000)	(1,191,524)
Forfeited or expired, Weighted Average Exercise Price (in dollars per share)	$ 3.88	$ 3.71
Exercised, options (in shares)	(10,000)
Exercised, Weighted Average Exercise Price (in dollars per share)	$ 0.81
Outstanding, options (in shares)	2,266,667	2,416,667
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 3.73	$ 3.75
Exercisable, options (in shares)	2,224,167
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 3.74
Share-Based Payment Arrangement, Nonemployee [Member]
Outstanding, options (in shares)	25,000	25,000
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 4	$ 4
Number of options granted (in shares)	0	0
Weighted-average exercise price per share (in dollars per share)	$ 0	$ 0
Forfeited or expired, options (in shares)	0	0
Forfeited or expired, Weighted Average Exercise Price (in dollars per share)	$ 0	$ 0
Exercised, options (in shares)	0	0
Exercised, Weighted Average Exercise Price (in dollars per share)	$ 0	$ 0
Outstanding, options (in shares)	25,000	25,000
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 4	$ 4
Exercisable, options (in shares)	25,000
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 4