Note 19 - Stock Options (Tables)

12 Months Ended

Dec. 31, 2024

Notes Tables

Share-based Arrangement Plans, Approval and Available Shares [Table Text Block]

			# Available
	# Approved by		December 31,
Stockholder approved plan	Stockholders		2024
2012 Share Incentive Plan		750,000		—
2015 Executive and Employee Stock Option Plan		2,000,000		260,000
2017 Executive and Employee Stock Option Plan		3,000,000		290,000
2019 Share Incentive Plan		2,000,000		270,000
2021 Share Incentive Plan		1,375,000		180,000
2023 Share Incentive Plan		1,600,000		880,000

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

				Weighted average
	Number of options			exercise price
Outstanding at December 31, 2022		6,520,444		$	7.12
Granted		1,527,865			2.63
Exercised		(57,000	)		2.65
Canceled and forfeited		(648,426	)		6.18
Outstanding at December 31, 2023		7,342,883		$	6.31
Granted		1,587,929			2.26
Exercised		(569	)		2.50
Canceled and forfeited		(1,291,785	)		6.09
Outstanding at December 31, 2024		7,638,458		$	5.50

	Number of options			Weighted average grant date fair value
Non-vested at December 31, 2023		2,055,781		$	3.90
Granted		1,587,929			1.74
Vested		(1,108,650	)		4.17
Forfeited		(414,413	)		2.16
Non-vested at December 31, 2024		2,120,647		$	2.49

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

	2024 Grants		2023 Grants
Exercise price	1.02 - 2.42		2.50 - 4.21
Risk-free rate		3.9% - 4.2%		3.6% - 4.3%
Expected dividend yield		—		—
Expected volatility		92.1% - 95.1%		85.8% - 88.4%
Expected term (in years)		6		6