Note 11 - Warrants (Details) - Fair Value of Warrants Assumptions	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Note 11 - Warrants (Details) - Fair Value of Warrants Assumptions [Line Items]
Risk-free interest rate		0.73%
Expected volatility		92.00%
Expected life (in years)		1 year 47 days
Expected forfeiture rate	0.00%	0.00%
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Note 11 - Warrants (Details) - Fair Value of Warrants Assumptions [Line Items]
Risk-free interest rate	0.36%
Expected volatility	103.40%
Expected life (in years)	328 days
Maximum [Member]
Note 11 - Warrants (Details) - Fair Value of Warrants Assumptions [Line Items]
Risk-free interest rate	1.41%
Expected volatility	147.30%
Expected life (in years)	4 years 255 days

No authoritative reference available.

No definition available.

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- Details

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- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

+ Details

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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