Note 9 - Leases - Summary of Components of Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Lease cost
Operating lease cost	$ 52	$ 60	$ 141	$ 185
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	43	62	123	187
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	0	0	248	0
Finance leases	$ 0	$ 0	$ 0	$ 0