Note 9 - Preferred Stock and Common Stock Warrants (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Allocation of Net Cash Proceeds [Table Text Block]

				Year Ended December 31, 2021
						Series C
				Series C		Preferred
				Warrants		Stock
Gross proceeds	$	39,500
Equity issuance costs		(62	)
Net proceeds - Initial Fair Value Allocation	$	39,438		$	1,631	$	37,807
Per balance sheet upon issuance				$	1,631	$	37,807

Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]

	December 31,			December 31,
	2021			2020
Stock price	$	2.85		$	2.09
Exercise price	$	0.01		$	0.01
Risk-free rate		0.1	%		0.1	%
Volatility		62.6	%		58.6	%
Term (years)		1.6			0.8