Note 11 - Equity Incentive Plan (Tables)

3 Months Ended

Mar. 31, 2023

Notes Tables

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

	Three Months Ended March 31,
	2023		2022
Cost of revenue	$	184	$	176
Research and development		517		367
Selling, general and administrative		3,016		2,002
Total stock-based compensation expense	$	3,717	$	2,545

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

						Weighted
						Average
				Weighted		Remaining		Aggregate
				Average		Contractual		Intrinsic
	Number of			Exercise		Term		Value
	Options			Price		(in years)		(in thousands)
Outstanding as of December 31, 2022		1,530,703		$	34.93
Granted		339,145		$	29.68
Exercised		(637	)	$	10.87			$	13
Forfeited and canceled		(11,212	)	$	39.77
Outstanding as of March 31, 2023		1,857,999		$	33.95		8.2	$	632
Vested, March 31, 2023		915,798		$	37.08		7.4	$	82
Vested or expected to vest, March 31, 2023		1,857,999		$	33.95		8.2	$	632

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

		Three Months Ended
		March 31,
	2023									2022
Risk free interest rate		3.5	%		-			4.3	%		1.3	%		-		1.9	%
Expected volatility		48.7	%		-			49.4	%		53.8	%		-		54.6	%
Expected life (years)					4.5									4.5
Expected dividend yield					0.0	%								0.0	%
Fair value per option				$	11.71		$						$	11.37

Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

				Weighted
	Number of			Average
	Shares			Fair Value
Outstanding as of December 31, 2022		675,405		$	28.40
Granted		368,169		$	26.91
Vested		(177,611	)	$	28.98
Forfeited and cancelled		(15,010	)	$	27.34
Outstanding as of March 31, 2023		850,953		$	27.65

Schedule of Nonvested Performance-Based Units Activity [Table Text Block]

	Number of Shares			Weighted Average Fair Value
Outstanding as of December 31, 2022		117,897		$	34.98
Forfeited and cancelled		(117,897	)	$	34.98
Outstanding as of March 31, 2023		-		$	-