Note 9 - Equity, Share-based Compensation and Warrants - Share-based Compensation Expenses Related to Employees and Directors (Details) - The 2014 Equity Incentive Plan [Member] - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Compensation expense related to common stock awards issued under equity incentive plans	$ 146	$ 241
Share-Based Payment Arrangement, Option [Member]
Compensation expense related to common stock awards issued under equity incentive plans	21	29
Restricted Stock Units (RSUs) [Member]
Compensation expense related to common stock awards issued under equity incentive plans	$ 125	$ 212