Note 11 - Stock Based Compensation (Details) - Stock Option and Restricted Stock Awards (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 30, 2013	Dec. 31, 2010
Stock Option and Restricted Stock Awards [Abstract]
Outstanding	861,905	725,529		900,000	691,809
Outstanding	$ 12.29	$ 14.63			$ 16.88
Outstanding	7 years 6 months
Exercisable at December 31, 2014	990,936
Exercisable at December 31, 2014	$ 9.71
Exercisable at December 31, 2014	6 years 36 days
Granted	1,014,700	187,777	145,611
Granted	$ 3.53	$ 4.39	$ 10.08
Exercised		(12,429)	(47,575)
Exercised		$ 14.67	$ 14.67
Cancelled or expired	(131,850)	(38,972)	(64,316)
Cancelled or expired	$ 19.05	$ 16.79	$ 29.43
Outstanding	1,744,755	861,905	725,529	900,000	691,809
Outstanding	$ 7.20	$ 12.29	$ 14.63		$ 16.88
Outstanding	7 years 6 months

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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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.

+ References

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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For presentations that combine terminations, 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 or that expired.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)-(4)

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Weighted average price of options that were either forfeited or expired.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Subparagraph (c)(1)(iv)(3)-(4)

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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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 remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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- Definition

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

+ References

No definition available.

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

+ References

No definition available.

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

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