Note 12 - Income Taxes (Details) - Operating Loss and Tax Credit Carry Forwards (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Federal:
Operating losses (expiring through 2032)	$ 31,308
Research tax credits (expiring through 2025)	168
Alternative minimum	28
State:
Net operating losses - Tennessee (expiring in 2027)	425
State [Member]
Federal:
Alternative minimum	$ 21

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

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-Glossary Alternative Minimum Tax

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