Note 5 - Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2024

Notes Tables

Schedule of Capital Reserved for Future Issuance [Table Text Block]

Stock options outstanding under 2019 Equity Incentive Plan	694,527
Restricted stock units outstanding under 2019 Equity Incentive Plan	358,607
Performance stock units outstanding under 2019 Equity Incentive Plan, at target	462,409
Shares authorized for future issuance under 2019 Equity Incentive Plan	3,682,511
Shares authorized for future issuance under 2019 Employee Stock Purchase Plan	1,360,964
Total	6,559,018

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
	2024		2023		2024		2023
	(in thousands)				(in thousands)
Stock-Based Compensation	$	3,968	$	3,697	$	7,789	$	7,147

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

	Number of shares			Weighted-average exercise price		Weighted-average remaining contractual term (in years)		Aggregate intrinsic value (in thousands)
Outstanding at January 1, 2024		807,685		$	34.31		—	$	—
Options granted		—			—
Options exercised		(104,525	)		37.96
Options cancelled		(8,633	)		74.57
Outstanding at June 30, 2024		694,527		$	33.26		5.3	$	34,708
Vested and Exercisable at June 30, 2024		669,188		$	32.32		5.3	$	34,081

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

	Number of shares			Weighted-average grant date fair value
Outstanding at January 1, 2024		332,077		$	61.07
Granted		121,556			65.10
Released		(84,675	)		55.43
Forfeited		(10,351	)		52.55
Non-vested outstanding at June 30, 2024		358,607		$	64.01

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

	Number of shares			Weighted-average grant date fair value
Outstanding at January 1, 2024		423,621		$	38.90
Granted		57,012			65.78
Vested		(12,645	)		96.74
Forfeited		(5,579	)		50.12
Non-vested outstanding at June 30, 2024		462,409		$	40.50