Note 9 - Income Taxes Income Tax (Details) $ in Millions	Sep. 30, 2017 USD ($)
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	$ 297.4
Deferred Tax Assets, Tax Credit Carryforwards, Research	6.4
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax	36.2
State and Local NOL Carryforwards [Member]
Operating Loss Carryforwards [Line Items]
Valuation Allowance, Amount	$ 64.1

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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