Note 16 - Shareholders' Equity - Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details) - € / shares	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Non-vested options granted (in shares)	575,000	0	0
Employee Stock Option [Member]
Outstanding - number (in shares)	917,188	1,095,850	1,310,850
Outstanding - Weighted average exercise price (in EUR per share)	€ 2.79	€ 2.76	€ 2.70
Non-vested options granted (in shares)	575,000
Granted - Weighted average exercise price (in EUR per share)	€ 3.22
Exercised - number (in shares)		(72,412)	(750)
Exercised - Weighted average exercise price (in EUR per share)		€ 2.13	€ 3.99
Forfeited - number (in shares)	(64,750)	(106,250)	(90,250)
Forfeited - Weighted average exercise price (in EUR per share)	€ 3.30	€ 2.88	€ 2.07
Expired - number (in shares)			(124,000)
Expired - Weighted average exercise price (in EUR per share)			€ 2.60
Outstanding - number (in shares)	1,427,438	917,188	1,095,850
Outstanding - Weighted average exercise price (in EUR per share)	€ 2.94	€ 2.79	€ 2.76
Exercisable - number (in shares)	774,938	724,688	784,600
Exercisable on December 31, (in EUR per share)	€ 2.87	€ 3.03	€ 3.09
Shares purchase options available for grant - number (in shares)	243,428	232,428	232,428

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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