Note 11 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 73,000	$ 127,000	$ 33,000	$ 105,000
Effective Income Tax Rate Reconciliation, Percent, Total	20.20%	(13.00%)	(1.60%)	(5.30%)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Unrecognized Tax Benefits, Ending Balance	$ 0		$ 0