Note 6 - Income Taxes (Details Textual) - USD ($)	6 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Foreign Tax Authority [Member] \| Ministry of the Economy, Finance and Industry, France [Member] \| Tax Year 2011 [Member]
Income Tax Examination, Year under Examination	2011
Foreign Tax Authority [Member] \| Ministry of the Economy, Finance and Industry, France [Member] \| Tax Year 2010 [Member]
Income Tax Examination, Year under Examination	2010
Foreign Tax Authority [Member] \| Ministry of the Economy, Finance and Industry, France [Member] \| Tax Year 2009 [Member]
Income Tax Examination, Year under Examination	2009
Foreign Tax Authority [Member] \| Ministry of the Economy, Finance and Industry, France [Member]
Liability for Uncertain Tax Positions, Current	$ 752,000
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	5,200,000
Liability for Uncertain Tax Positions, Current	$ 752,000	$ 810,000

Tax year being audited in the income tax examination, in CCYY format.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

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The current portion of the amount recognized for uncertain tax positions as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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