Note 10 - Stock Based Compensation (Details) - Fair Value of Option Assumptions	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Note 10 - Stock Based Compensation (Details) - Fair Value of Option Assumptions [Line Items]
Risk-free interest rate	0.78%
Expected volatility	102.23%
Expected life (in years)	5 years
Expected forfeiture rate	0.00%
Minimum [Member]
Note 10 - Stock Based Compensation (Details) - Fair Value of Option Assumptions [Line Items]
Risk-free interest rate	0.85%	1.60%
Expected volatility	83.41%	80.80%
Expected life (in years)	5 years 3 months	5 years
Expected forfeiture rate	5.00%	0.00%
Maximum [Member]
Note 10 - Stock Based Compensation (Details) - Fair Value of Option Assumptions [Line Items]
Risk-free interest rate	1.19%	2.97%
Expected volatility	97.83%	82.30%
Expected life (in years)	6 years	6 years 109 days
Expected forfeiture rate	7.50%	7.50%

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No authoritative reference available.

+ References

No definition available.

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- Definition

Expected term of share-based compensation awards, 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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ 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 (f)(2)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ 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 (f)(2)(iv)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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