Note 13 - Summary of Stock Options (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Share-based Payment Arrangement, Option, Activity [Table Text Block]

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Options outstanding, January 1, 2021		986,399		$	19.10		8.9	$	675
Options granted		2,251,000		$	2.73
Options exercised		-
Options canceled		(64,296	)	$	17.85
Options outstanding, December 31, 2021		3,173,103		$	7.51		9.0	$	-
Vested and exercisable and expected to vest, December 31, 2021		2,947,472		$	7.83		9.0	$	-
Vested and exercisable, December 31, 2021		774,800		$	18.81		8.5	$	-

Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]

Range of Exercise Prices			Number Outstanding as of December 31, 2021		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)		Number Exercisable as of December 31, 2021		Weighted Average Exercise Price
$2.28	-	$2.96		2,208,063	$	2.73		9.5		259,301	$	2.73
$3.06	-	$3.40		10,000	$	3.20		9.2		-	$	-
$4.45	-	$4.80		11,900	$	4.72		8.9		3,088	$	4.71
$5.10	-	$5.40		88,000	$	5.28		8.8		62,219	$	5.34
$6.90	-	$6.90		5,400	$	6.90		8.3		2,364	$	6.90
$8.60	-	$8.91		830,825	$	8.69		7.9		433,263	$	8.69
$10.90	-	$13.60		15,500	$	12.64		8.2		11,271	$	13.00
$380.00	-	$9,920.00		3,415	$	2,873.63		6.2		3,294	$	2,911.12
Total:				3,173,103	$	7.51		9.0		774,800	$	18.81

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Year Ended December 31,
	2021			2020
Expected term (in years)		6			5
Average volatility		76	%		82	%
Risk-free interest rate		0.97	%		0.37	%
Dividend yield		0	%		0	%

Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	Year Ended December 31,
	2021		2020
Cost of revenue	$	265	$	208
Research and development		456		325
Selling, general and administrative		3,058		2,118
Total	$	3,779	$	2,651