Note 10 - Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2015

Stockholders' Equity Note [Abstract]

Schedule of Share-based Compensation, Activity [Table Text Block]

	Warrants Outstanding			Weighted Average Exercise Price During Period
Outstanding at December 31, 2014		969,549		$	4.61
Exercised		(580,000	)		4.30
Cancelled/forfeited		(55,000	)		4.30
Expired		(240,000	)		5.34
Outstanding at March 31, 2015		94,549		$	4.82

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three months ended
	March 31,
	2015		2014
Cost of sales	$	3	$	2
Product development		3		(1	)
Selling, general, and administrative		106		122
Total stock-based compensation	$	112	$	123

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

	Three months ended
	March 31,
	2015			2014
Fair value of options issued	$	4.07		$	3.25
Exercise price	$	5.47		$	4.23
Expected life of option (in years)		5.9			5.6
Risk-free interest rate		1.7	%		1.8	%
Expected volatility		91.3	%		98.0	%
Dividend yield		0	%		0	%

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

	Number of Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Life (in years)
Outstanding at December 31, 2014		459,271		$	8.95
Granted		208,500			5.47
Exercised		(321	)		2.30
Cancelled/forfeited		(47,947	)		6.35
Outstanding at March 31, 2015		619,503		$	7.98		8.5
Vested and expected to vest at March 31, 2015		545,159		$	7.35		8.4
Exercisable at March 31, 2015		304,654		$	10.71		7.5

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

	Restricted Stock Units		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Life (in years)
Outstanding at December 31, 2014		-	$	-
Granted		60,750		5.47
Outstanding at March 31, 2015		60,750	$	5.47		2.0