Note 4 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Jul. 18, 2016	Nov. 24, 2015	Nov. 25, 2014
Delphax [Member]
Business Acquisition, Percentage of Voting Interests Acquired						38.00%
Contrail Aviation Inc. [Member] | Contrail Aviation Support LLC. [Member]
Business combination, Equity Interests in Acquiree, Percentage					21.00%
Business Combination, Equity Interest in Acquiree, Deemed to be Acquired, Percentage					79.00%
Delphax [Member] | Foreign Tax Authority [Member]
Operating Loss Carryforwards		$ 6,000,000		$ 6,000,000
Tax Credit Carryforward, Amount	$ 4,500,000		$ 4,500,000
Delphax [Member] | Domestic Tax Authority [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount		4,500,000		4,500,000
Delphax [Member] | Domestic Tax Authority [Member] | Alternative Minimum Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount		325,000		325,000
Delphax [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards		7,900,000		7,900,000
Tax Credit Carryforward, Amount	3,200,000		3,200,000
Income Tax Expense (Benefit)	375,000	$ 1,701,000	$ 3,000	$ 1,368,000
Effective Income Tax Rate Reconciliation, Percent			0.10%	30.90%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		34.00%
Deferred Tax Assets, Valuation Allowance	$ 12,770,000		$ 12,770,000				$ 11,661,000