Note 9 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%					35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			$ (16,000,000)
Income Tax Expense (Benefit), Continuing Operations, Revaluation Differences in Deferred Taxes			(20,000,000)
Income Tax Expense (Benefit), Total	$ (100,000)	$ (4,240,000)	(16,950,000)	$ (4,550,000)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest, Total			$ (2,443,000)	3,042,000
Liability For Uncertain Tax Positions, Reversal		2,665,000		2,665,000
Unrecognized Tax Benefits, Accumulated Reduction		$ 743,000		743,000
Deferred Tax Liability, Reversal				$ 352,000
Effective Income Tax Rate Reconciliation, Percent, Total			694.00%	150.00%
Domestic Tax Authority [Member] | Earliest Tax Year [Member]
Open Tax Year			2015
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Open Tax Year			2013
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent					24.28%