Note 13 - Stock Compensation Plan (Tables)

12 Months Ended

Dec. 31, 2019

Notes Tables

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

	December 31,
	2019		2018
Expected volatility		-		64.92%	-	99.30%
Expected dividends					-
Expected term (in years)		-		0.50	-	6.20
Risk-free rate		-		2.07%	-	2.97%

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

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
								(in thousands)
Options outstanding at December 31, 2017		34,434,994		$	0.17
Granted		9,127,175			0.17
Exercised		(5,438,716	)		0.09
Forfeited		(8,479,583	)		0.21
Expired		(812,700	)		0.29
Options outstanding at December 31, 2018		28,831,170			0.17
Granted		-			-
Exercised		(243,125	)		0.09
Forfeited		(8,796,775	)		0.18
Expired		(450,158	)		0.20
Options outstanding at December 31, 2019		19,341,112		$	0.17		6.4	$	118
Options exercisable at December 31, 2019		13,455,439		$	0.18		5.6	$	100
Options unvested at December 31, 2019		5,885,673		$	0.16		8.2	$	18
Options vested or expected to vest at December 31, 2019		17,919,954		$	0.17		6.2	$	117

Schedule of Supplemental Stock Option Data [Table Text Block]

	December 31,
	2019		2018
Weighted average grant date fair value per option granted	$	-	$	0.13
Fair value of options vested		644		911
Cash from participants to exercise stock options		21		463
Intrinsic value of options exercised		13		537

Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]

Options Outstanding										Options Exercisable
Range of Exercise Prices				Numbers of Options Outstanding		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Number of Options Exercisable		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price
	$0.00	-	0.10		4,093,777		4.86	$	0.07		3,550,111		4.66	$	0.07
	$0.11	-	0.38		15,247,335		6.83		0.20		9,905,328		5.98		0.21
		Total			19,341,112						13,455,439