Note 9 - Prepaid and Other Current Assets (Details Textual) - USD ($) $ in Millions	3 Months Ended			9 Months Ended	12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Employee Retention Credits Receivable						$ 3.3
Proceeds From Employee Retention Credit				$ 3.0
Cost of Sales [Member]
Employee Retention Credits Benefit					$ 1.8
Selling, General and Administrative Expenses [Member]
Employee Retention Credits Benefit					0.8
Research and Development Expense [Member]
Employee Retention Credits Benefit					0.7
Prepaid Expenses and Other Current Assets [Member]
Employee Retention Credits Receivable					$ 3.3
Maximum [Member]
Percentage of Qualified Wages Paid	70.00%	70.00%	50.00%