Note 2 - Summary of significant accounting policies (Detail) - The Company has excluded the following outstanding warrants and options from the calculation of diluted earnings per share	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Antidilutive Securities	15,344,748	11,887,132
Warrant [Member]
Antidilutive Securities	10,377,995	7,533,620
Stock Options [Member]
Antidilutive Securities	4,966,753	4,353,512

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details