Note 13 - Equity-based Compensation (Tables)

6 Months Ended

Jun. 30, 2020

Notes Tables

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

(in thousands, except years and per share data)	Options			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (years)		Aggregate Intrinsic Value
Outstanding at December 31, 2019		2,183		$	4.03		6.6	$	43
Options granted		520		$	0.97
Restricted stock units granted		160		$	—
Options exercised		-		$	—
Restricted stock units vested		(3	)	$	—
Options forfeited/cancelled		(167	)	$	5.83
Restricted stock units cancelled		(1	)	$	—
Outstanding at June 30, 2020		2,692		$	3.10		6.97	$	384
Vested and expected to vest at June 30, 2020		2,573		$	3.20		6.84	$	336
Vested at June 30, 2020		1,848		$	4.04		5.85	$	—
Exercisable at June 30, 2020		1,848		$	4.04		5.85	$	—

Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2020		2019		2020		2019
Research and development	$	7	$	13	$	14	$	24
Sales and marketing		11		27		20		46
General and administrative		108		83		149		167
Total stock-based compensation expense	$	126	$	123	$	183	$	237

Employees and Directors [Member]

Notes Tables

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

	Six Months Ended June 30,
Assumption	2020			2019
Expected price volatility		159.81	%		106.86	%
Expected term (in years)		6.43			6.16
Risk-free interest rate		0.50	%		2.08	%
Dividend yield		0.00	%		0.00	%
Weighted-average fair value of options granted during the period	$	0.93		$	0.27