Note 11 - Warrants (Detail) - Fair Value of Warrants Assumptions	1 Months Ended	12 Months Ended
Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Risk-free interest rate	1.10%	0.73%	0.83%	2.02%
Expected volatility	74.30%	92.02%	75.17%	63.50%
Expected life (in years)	3 years 6 months	1 year 47 days	1 year 219 days	2 years 36 days
Expected forfeiture rate		0.00%	0.00%	0.00%
Expected dividend yield		0.00%	0.00%	0.00%

No authoritative reference available.

No definition available.

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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=7578670&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

Name:	us-gaap_FairValueAssumptionsExpectedVolatilityRate
Namespace Prefix:	us-gaap_
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- Definition

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

+ References

+ Details

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