Note 14 - Stock-based Compensation - Summary of Option Activity (Details) - $ / shares	3 Months Ended
Jun. 30, 2017	Mar. 31, 2017
Outstanding, options (in shares)	16,203,385	16,203,385
Outstanding, weighted average exercise price (in dollars per share)	$ 0.38	$ 0.38
Granted, options (in shares)	5,550,000
Granted, weighted average exercise price (in dollars per share)	$ 0.11
Exercised, options (in shares)
Exercised, weighted average exercise price (in dollars per share)
Cancelled, options (in shares)
Cancelled, weighted average exercise price (in dollars per share)
Forfeited or expired, options (in shares)	(160,000)
Forfeited or expired, weighted average exercise price (in dollars per share)	$ 0.22
Outstanding, options (in shares)	21,593,385	16,203,385
Outstanding, weighted average exercise price (in dollars per share)	$ 0.31	$ 0.38
Exercisable, options (in shares)	21,593,385
Exercisable, weighted average exercise price (in dollars per share)	$ 0.31

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.

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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.

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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.

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Number of options outstanding, including both vested and non-vested options.

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

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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