Note 20 - Income Taxes - Difference in Income Tax Provision (Details) - USD ($)	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Expected Federal income tax expense U.S. statutory rate	$ 978,000	$ 818,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	30.80%
State income taxes, net of federal benefit	$ 171,000	$ 129,000
State income taxes, net of Federal benefit, percentage	3.70%	4.90%
Permanent differences, other	$ (61,000)	$ 21,000
Permanent differences, other, percentage	(1.30%)	0.80%
Micro-captive insurance benefit	$ (197,000)	$ (320,000)
Micro-captive insurance benefit, percentage	(4.20%)	(12.10%)
Change in valuation allowance	$ 1,405,000	$ (1,116,000)
Change in valuation allowance, percentage	30.20%	(42.10%)
Domestic production activities deduction		$ (15,000)
Domestic production activities deduction, percentage	0.00%	(0.60%)
Income attributable to minority interest - Contrail Aviation	$ (434,000)	$ (79,000)
Income Attributable to Minority Interest - Contrail Aviation, percentage	(9.30%)	(3.00%)
Bargain purchase gain	$ (417,000)	$ (155,000)
Bargain purchase gain, percentage	(9.00%)	(5.80%)
Tax rate change applied to deferreds		$ 2,297,000
Tax rate change applied to deferreds, percentage	0.00%	86.60%
Deferred benefit for outside basis difference recorded on Delphax CFCs	$ 31,000	$ (811,000)
Deferred benefit for outside basis difference recorded on Delphax CFCs, percentage	0.70%	(30.60%)
Deferred benefit for increase in Canadian tax credits for Delphax		$ (149,000)
Deferred benefit for increase in Canadian tax credits for Delphax, percentage	0.00%	(5.60%)
Recognition of AMT tax credits as tax receivable		$ (311,000)
Recognition of AMT tax credits as tax receivable, percentage	0.00%	(11.70%)
Other differences, net	$ 26,184	$ (114,000)
Other differences, net, percentage	0.60%	4.30%
Total	$ 1,502,184	$ 195,000
Income tax expense, percentage	32.40%	7.30%