Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2017

Stockholders' Equity Note [Abstract]

Schedule of Warrants

	Warrants Outstanding		Weighted Average ExercisePrice During Period
Balance, December 31, 2014	969,549		4.61
Warrants exercised	(638,189	)	4.58
Warrants cancelled/forfeited	(112,110	)	5.54
Warrants expired	(205,000	)	4.20
Balance, December 31, 2015	14,250		4.30
Warrants cancelled/forfeited	(7,500	)	4.30
Balance, December 31, 2016	6,750		$	4.30
Warrants cancelled/forfeited	(6,750	)	$	4.30
Balance, December 31, 2017	—		$	—

Summary of Impact of Results of Stock-Based Compensation

The impact on our results for stock-based compensation was as follows (in thousands): 

	For the year ended December 31,
	2017		2016		2015
Cost of sales	$	34	$	56	$	38
Product development	59		84		37
Selling, general, and administrative	714		1,220		738
Total stock-based compensation	$	807	$	1,360	$	813

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions

Estimates utilized in the calculation include the expected life of the option, risk-free interest rate, and expected volatility, and are further comparatively detailed as follows:

	2017			2016			2015
Fair value of options issued	$	2.66		$	5.27		$	5.33
Exercise price	$	3.55		$	7.46		$	7.23
Expected life of option (in years)	5.8			5.8			5.8
Risk-free interest rate	2.1		%	1.5		%	1.7		%
Expected volatility	91.9		%	93.7		%	90.7		%
Dividend yield	0.00		%	0.00		%	0.00		%

Summary of Option Activity

A summary of option activity under all plans was as follows:

	Number of Options		Weighted Average Exercise Price Per Share
Outstanding at December 31, 2014	459,271		$	8.95
Granted	340,500		8.65
Cancelled	(147,152	)	10.10
Exercised	(50,412	)	4.69
Outstanding at December 31, 2015	602,207		8.58
Granted	167,819		7.31
Cancelled	(160,126	)	12.94
Exercised	(79,166	)	4.48
Outstanding at December 31, 2016	530,734		7.48
Granted	192,984		3.55
Cancelled	(377,095	)	6.71
Expired	(56,111	)	10.65
Exercised	(42,000	)	2.30
Outstanding at December 31, 2017	248,512		$	5.76
Vested and expected to vest at December 31, 2017	228,880		$	5.97
Exercisable at December 31, 2017	110,476		$	8.63

Schedule of Options Outstanding

The options outstanding at December 31, 2017 have been segregated into ranges for additional disclosure as follows:

OPTIONS OUTSTANDING							OPTIONS EXERCISABLE
Range ofExercise Prices			Number of Shares Outstanding	Weighted Average Remaining Contractual Life (in years)	Weighted Average Exercise Price		Number of Shares Exercisable	Weighted Average Remaining Contractual Life (in years)	Weighted Average Exercise Price
$2.30	—	$3.25	59,558	9.1	$	3.04	2,000	4.9	$	2.45
$3.26	—	$4.00	74,165	9.2	3.43		—	9.2	3.43
$4.01	—	$5.50	51,919	6.6	4.96		50,461	6.6	4.94
$5.51	—	$20.00	62,870	6.0	11.75		58,015	5.8	12.05
			248,512	7.8	$	5.76	110,476	6.1	$	8.63

Summary of Restricted Stock Activity

The following table shows a summary of restricted stock and restricted stock unit activity:

	Restricted Stock Units Outstanding		Weighted Average Grant Date Fair Value
At December 31, 2014	—		—
Granted	73,750		6.92
Forfeited	(16,250	)	5.54
At December 31, 2015	57,500		$	7.31
Granted	290,966		6.56
Vested	(11,213	)	14.18
Forfeited	(87,138	)	6.73
At December 31, 2016	250,115		$	6.34
Granted	375,542		$	3.18
Vested	(115,622	)	$	5.78
Forfeited	(203,893	)	$	5.30
At December 31, 2017	306,142		$	3.37