Note 8 - Income Taxes (Details Textual) - USD ($)	3 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Income Tax Expense (Benefit), Total	$ 1,360,000	$ 2,013,000
Effective Income Tax Rate Reconciliation, Percent, Total	23.50%	20.60%
Proceeds from Income Tax Refunds		$ 285,000