Note 14 - Stock Based Compensation - Stock Option Activity (Details) - The 2010 Stock Option and Incentive Plan [Member]	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Outstanding, shares (in shares) | shares	783,383
Outstanding, weighted average exercise price per share (in dollars per share) | $ / shares	$ 12.14
Granted, shares (in shares) | shares	3,565,000
Granted, weighted average exercise price per share (in dollars per share) | $ / shares	$ 1.51
Granted | $	$ 3,667,300
Forfeited, shares (in shares) | shares	(40,000)
Forfeited, weighted average exercise price per share (in dollars per share) | $ / shares	$ 2.38
Outstanding, shares (in shares) | shares	4,308,383
Outstanding, Weighted average exercise price per share (in dollars per share) | $ / shares	$ 3.44
Outstanding, weighted average contractual life remaining in years (Year)	9 years 14 days
Outstanding, aggreate instrinsic value | $	$ 651,000
Exercisable, shares (in shares) | shares	3,500,186
Exercisable, Weighted average exercise price per share (in dollars per share) | $ / shares	$ 3.74
Exercisable, weighted average contractual life remaining in years (Year)	9 years 18 days
Exercisable, aggreate instrinsic value | $	$ 569,625
Vested and expected to vest, shares (in shares) | shares	4,308,383
Vested and expected to vest, Weighted average exercise price per share (in dollars per share) | $ / shares	$ 3.44
Vested and expected to vest, weighted average contractual life remaining in years (Year)	9 years 14 days
Vested and expected to vest, aggreate instrinsic value | $	$ 651,000