Note 4 - Stock-based Compensation (Tables)

6 Months Ended

Jun. 30, 2022

Notes Tables

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

	Six Months Ended June 30, 2022
	Number of Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Outstanding, January 1, 2022		919,790		$	5.67		6.5	$	—
Granted		12,500			0.83
Cancelled/Forfeited		(152,455	)		2.38
Expired		(53,755	)		29.32
Outstanding, June 30, 2022		726,080		$	4.52		6.0	$	—
Exercisable, June 30, 2022		545,665		$	5.52		4.9	$	—

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

	Six Months Ended June 30, 2022
	Number of Shares			Weighted Average Grant-Date Fair Value
Unvested, January 1, 2022		95,000		$	1.40
Vested		(5,000	)		1.96
Unvested, June 30, 2022		90,000		$	1.37