Note 18 - Income Taxes - Difference in Income Tax Provision (Details) - USD ($)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Expected Federal income tax expense U.S. statutory rate	$ 818,000	$ (1,434,000)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	30.79%	34.00%
State income taxes, net of Federal benefit	$ 129,000	$ 40,000
State income taxes, net of Federal benefit, percentage	4.90%	(0.90%)
Permanent differences, other	$ 21,000	$ 156,000
Permanent differences, other, percentage	0.80%	(3.70%)
Dividend received deduction		$ (302,000)
Dividend Received Deduction, percentage	0.00%	7.20%
Section 831(b) benefit	$ (320,000)	$ (281,000)
Section 831(b) benefit, percentage	(12.10%)	6.70%
Change in valuation allowance	$ (1,116,000)	$ 3,868,000
Change in valuation allowance, percentage	(42.10%)	(91.80%)
Domestic production activities deductions	$ (15,000)	$ (64,000)
Domestic production activities deductions, percentage	(0.60%)	1.50%
Income attributable to minority interest - Contrail Aviation	$ (79,000)	$ (45,000)
Income Attributable to Minority Interest - Contrail Aviation, percentage	(3.00%)	1.10%
Bargain purchase gain	$ (155,000)
Bargain purchase gain, percentag	(5.80%)	0.00%
Tax rate change applied to deferreds	$ 2,297,000
Tax rate change applied to deferreds, percentag	86.60%	0.00%
Deferred benefit for outside basis difference recorded on Delphax CFC's	$ (811,000)	$ (1,015,000)
Deferred benefit for outside basis difference recorded on Delphax CFC's, percentage, percentag	(30.60%)	24.10%
Deferred benefit for increase in Canadian tax credits for Dephax	$ (149,000)
Deferred benefit for increase in Canadian tax credits for Dephax, percentag	(5.60%)
Recognition of AMT credit as tax receivable	$ (311,000)
Recognition of AMT credit as tax receivable, percentag	(11.70%)	0.00%
Deferred state income taxes, net of Federal benefit for Delphax		$ (102,000)
Deferred state income taxes, net of Federal benefit for Delphax, percentage	0.00%	2.40%
Other differences, net	$ (114,000)	$ (96,000)
Other differences, net, percentage	(4.30%)	2.30%
Total	$ 195,000	$ 725,000
Income tax expense, percentage	7.30%	(17.10%)