Note 3 - Income Taxes (Details Textual)				1 Months Ended	3 Months Ended
	May 02, 2017 USD ($)	Jul. 18, 2016 USD ($)	Nov. 24, 2015 USD ($)	May 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)
Income Tax Expense (Benefit)					$ 374,000	$ (372,000)
Effective Income Tax Rate Reconciliation, Percent					23.30%	4.40%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent					34.00%
Estimated Future Liquidation Loss on Tax Attributes					$ 2,900,000
Deferred Tax Assets, Valuation Allowance			$ 11,661,000		13,809,000	$ 12,772,000
Deferred Income Tax Expense (Benefit)					(501,880)
Business Combination, Bargain Purchase, Gain Recognized, Amount, Net					$ 501,880
Canada, France, and United Kingdom [Member]
Number of Foreign Subsidiaries					3
Delphax [Member]
Business Acquisition, Percentage of Voting Interests Acquired			38.00%
Payments to Acquire Businesses, Gross			$ 1,050,000
Delphax [Member] | Foreign Tax Authority [Member]
Operating Loss Carryforwards							$ 6,300,000
Delphax [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards							13,200,000
Delphax [Member] | Domestic Tax Authority [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount							4,300,000
Delphax [Member] | Domestic Tax Authority [Member] | Alternative Minimum Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount							$ 311,000
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%
Payments to Acquire Businesses, Gross		$ 4,033,368
Acquired Inventory and Principal Business Assets, and Assumed Specified Liabilities, of Aircraft Instrument and Radio Company, Incorporated, and Aircraft Instrument and Radio Services, Inc. [Member] | AirCo [Member]
Payments to Acquire Businesses, Gross	$ 2,400,000			$ 2,400,000
Business Combination, Bargain Purchase, Gain Recognized, Amount	$ 779,880
Deferred Tax Liabilities, Net					$ 278,000
Deferred Income Tax Expense (Benefit)					278,000
Business Combination, Bargain Purchase, Gain Recognized, Amount, Net					$ 502,000