Note 17 - Income Taxes - Difference in Income Tax Provision (Details) - USD ($)	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Expected Federal income tax expense U.S. statutory rate	$ 2,092,000	$ 1,161,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	34.00%	34.00%
State income taxes, net of Federal benefit	$ 169,000	$ 67,000
State income taxes, net of Federal benefit, percentage	2.70%	2.00%
Permanent differences, other	$ 47,000	$ 42,000
Permanent differences, other, percentage	0.80%	1.20%
Section 831(b) benefit	$ (316,000)	$ (364,000)
Section 831(b) benefit, percentage	(5.10%)	(10.60%)
Change in valuation allowance	$ 557,000
Change in valuation allowance, percentage	9.00%
Domestic production activities deductions	$ (193,000)	$ (107,000)
Domestic production activities deductions, percentage	(3.10%)	(3.10%)
Other differences, net	$ 39,000	$ 132,000
Other differences, net, percentage	0.60%	3.80%
Total	$ 2,395,452	$ 931,000
Income tax expense, percentage	38.90%	27.30%