Note 5 - Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2024

Notes Tables

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

Stock options outstanding under 2019 Equity Incentive Plan	749,239
Restricted stock units outstanding under 2019 Equity Incentive Plan	358,002
Performance stock units outstanding under 2019 Equity Incentive Plan, at target	461,037
Shares authorized for future issuance under 2019 Equity Incentive Plan	3,694,726
Shares authorized for future issuance under 2019 Employee Stock Purchase Plan	1,360,964
Total	6,623,968

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

	Three Months Ended March 31,
	2024		2023
	(in thousands)
Stock-Based Compensation	$	3,820	$	3,450

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		(52,722	)		35.22
Options canceled		(5,724	)		67.05
Outstanding at March 31, 2024		749,239		$	33.99		5.7	$	38,564
Vested and Exercisable at March 31, 2024		709,725		$	32.56		5.6	$	37,551

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

	Number of shares			Weighted-average grant date fair value
Outstanding at January 1, 2024		333,716		$	61.01
Granted		105,370			62.60
Released		(72,900	)		56.05
Forfeited		(8,184	)		52.15
Non-vested outstanding at March 31, 2024		358,002		$	62.69

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		55,005			65.22
Vested		(12,645	)		96.74
Forfeited		(4,944	)		50.19
Non-vested outstanding at March 31, 2024		461,037		$	40.33