Note 10 - Share-based Compensation (Tables)

3 Months Ended

Mar. 31, 2022

Notes Tables

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

				Weighted Average
	Options on					Remaining		Aggregate
	Common			Exercise		Contractual		Intrinsic
	Shares			Price		Term		Value
Outstanding January 1, 2022		3,935,883		$	5.24		4.79
Granted		104,000		$	3.55
Exercised		(50,000	)	$	1.50
Forfeited, cancelled, expired		(388,912	)	$	5.01
Outstanding March 31, 2022		3,600,971		$	5.27		3.58	$	774
Exercisable March 31, 2022		2,549,388		$	2.86		2.03	$	761

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

	For the Three Months
	Ended March 31,
	2022			2021
Expected stock price volatility		49	%		50	%
Risk-free interest rate		1.57	%		0.89	%
Forfeiture rate		0	%		0	%
Expected dividend yield		0	%		0	%
Expected life of options - years		1.39			5.70
Weighted-average fair value of options granted	$	1.72		$	2.42

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

				Weighted Average		Weighted Average
	Service-Based			Grant Date		Vesting
	RSU's			Fair Value		Period (Years)
Unvested at January 1, 2022		269,303		$	6.47
Granted - service based		160,779		$	2.41
Vested		(49,252	)	$	4.72
Forfeited and cancelled		(23,357	)	$	4.19
Unvested at March 31, 2022		357,473		$	5.03	2.05

Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block]

	Three Months Ended March 31,
	2022		2021
Selling, general and administrative	$	894	$	602
Research and development		135		257
Total share-based expense	$	1,029	$	859