Note 7 - Stock-based Compensation and Option Plans (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

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

	2016			2017			2018
Weighted average value per option granted during the period	$	0.68		$	1.81		$	1.87
Assumptions:
Forfeiture rate (1)		4.2	%		2.0	%		1.7	%
Expected dividend yield (2)		0.0	%		0.0	%		0.0	%
Volatility (3)		71.1	%		67.6	%		66.5	%
Risk free interest rate (4)		1.7	%		2.2	%		2.9	%
Expected life (years) (5)		7.0			6.9			7.3
Fair value of options granted (in thousands)	$	2,307		$	574		$	841

Share-based Compensation, Stock Options, Activity [Table Text Block]

	Options			Weighted average		Weighted average		Intrinsic value
	(000s)			exercise price		remaining life		per share
Options outstanding December 31, 2015		6,808		$	2.89
Granted		2,265			1.02
Exercised		(83	)		1.40
Forfeited/Expired		(836	)		2.84
Options outstanding December 31, 2016		8,154		$	2.39
Granted		317			1.81
Exercised		(5	)		0.97
Forfeited/Expired		(149	)		3.58
Options outstanding December 31, 2017		8,317		$	2.35
Granted		300			2.80
Exercised		(379	)		1.71
Forfeited/Expired		(689	)		2.70
Options outstanding December 31, 2018		7,549		$	2.37		4.9	$	1.68
Exercisable at end of year		6,479		$	2.50		4.5	$	1.78

	2016		2017		2018
Weighted average grant date fair value of stock options granted (per share)	$	0.68	$	1.81	$	1.87
Total fair value of options vested (000's)	$	2,776	$	2,795	$	2,054
Total intrinsic value of options exercised (000's)	$	39	$	5	$	395

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

	Outstanding Options						Exercisable
			Weighted		Weighted				Weighted		Weighted
			average		average				average		average
	Number		remaining		exercise		Number		remaining		exercise
Range of stock option prices	Outstanding		life		price		Outstanding		life		price
0.97 - 1.99		3,270,117		4.9	$	1.26		2,490,367		4.2	$	1.32
2.00 - 2.99		1,422,975		4.4	$	2.44		1,319,725		4.0	$	2.43
3.00 - 3.99		2,212,606		5.4	$	3.29		2,025,106		5.3	$	3.30
4.00 - 4.99		544,750		4.2	$	4.54		544,750		4.2	$	4.54
5.00 - 5.99		98,000		5.4	$	5.38		98,000		5.4	$	5.38
6.00 - 6.28		1,000		5.5	$	6.28		1,000		5.5	$	6.28
		7,549,448		4.9	$	2.37		6,478,948		4.5	$	2.50

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

	Number of Shares			Weighted average grant date fair value
Unvested December 31, 2015		1,643,284		$	3.44
Granted		-			-
Vested/Released		(52,017	)		2.40
Forfeited		(98,802	)		3.63
Unvested December 31, 2016		1,492,465		$	3.47
Granted		44,000			1.75
Vested/Released		(56,340	)		3.14
Forfeited		(750	)		2.63
Unvested December 31, 2017		1,479,375		$	3.43
Granted		861,113			2.17
Vested/Released		(1,326,250	)		3.43
Forfeited		(187,557	)		3.22
Unvested December 31, 2018		826,681		$	2.15

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

	Number of Shares			Weighted average grant date fair value
Unvested December 31, 2017		-		$	-
Granted		464			2.37
Vested/Released		-			-
Forfeited		(59	)		2.37
Unvested December 31, 2018		405		$	2.37