Note 15 - Stockholders Equity - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Outstanding, number of shares (in shares)	4,433,392
Outstanding, weighted average exercise price (in dollars per share)	$ 4.59
Outstanding, weighted average remaining contractual term (Year)	7 years 2 months 12 days	6 years 2 months 12 days
Outstanding, aggregate intrinsic value	$ 136	$ 247
Options granted, number of shares (in shares)	2,664,500
Options granted, weighted average exercise price (in dollars per share)	$ 2.20
Options granted, aggregate intrinsic value	$ 0
Options exercised, number of shares (in shares)	(261,836)
Options exercised, weighted average exercise price (in dollars per share)	$ 2.34
Options exercised, aggregate intrinsic value	$ 92	$ 464
Options forfeited/cancelled, number of shares (in shares)	(858,877)
Options forfeited/cancelled, weighted average exercise price (in dollars per share)	$ 4.21
Options forfeited/cancelled, aggregate intrinsic value (in dollars per share)	$ 0
Outstanding, number of shares (in shares)	5,977,179	4,433,392
Outstanding, weighted average exercise price (in dollars per share)	$ 3.72	$ 4.59
Exercisable, number of shares (in shares)	2,907,668
Exercisable, weighted average exercise price (in dollars per share)	$ 4.52
Exercisable, weighted average remaining contractual term (Year)	5 years 3 months 7 days
Exercisable, aggregate intrinsic value	$ 136
Expected to vest, number of shares (in shares)	3,069,511
Expected to vest, weighted average exercise price (in dollars per share)	$ 2.97
Expected to vest, weighted average remaining contractual term (Year)	9 years 10 days
Expected to vest, aggregate intrinsic value	$ 0