v3.8.0.1

Note 18 - Income Taxes (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Expense (Benefit)			$ (701,000)	$ (34,000)	$ 760,000
Valuation Allowances and Reserves, Period Increase (Decrease)			(17,100,000)	14,200,000	$ 5,500,000
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax				$ 703,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%
Tax Adjustments, Settlements, and Unusual Provisions	(700,000)
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	0
Earliest Tax Year [Member]
Open Tax Year			2005
Latest Tax Year [Member]
Open Tax Year			2017
Subject to Expiration [Member]
Operating Loss Carryforwards	1,400,000		$ 1,400,000
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%
Research Tax Credit Carryforward [Member] | Subject to Expiration [Member]
Tax Credit Carryforward, Amount	26,000		26,000
Domestic Tax Authority [Member]
Operating Loss Carryforwards	115,600,000		115,600,000
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax	700,000		700,000
Domestic Tax Authority [Member] | Accounting Standards Update 2016-09 [Member]
Operating Loss Carryforwards	2,900,000		2,900,000
Domestic Tax Authority [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	5,900,000		5,900,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	97,200,000		97,200,000
State and Local Jurisdiction [Member] | Accounting Standards Update 2016-09 [Member]
Operating Loss Carryforwards	2,000,000		2,000,000
State and Local Jurisdiction [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	$ 3,600,000		$ 3,600,000

X

- Definition

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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