Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Activity under Stock-Based Compensation Plans

A summary of activity for the Company’s stock option plans for the three months ended March 31, 2019 follows:

	Number Outstanding			Average Exercise Price per Share		Weighted Average Remaining Contractual Term (Years)		Average Intrinsic Value
Balance at December 31, 2018		621,602		$	5.87		6.32	$	—
Granted		—			—
Cancelled or Expired		(46,000	)		8.52
Exercised
Balance at March 31, 2019		575,602		$	5.66		6.50	$	302,233
Vested or expected to vest at     March 31, 2019		574,705		$	5.66		6.56	$	301,623
Exercisable at March 31, 2019		520,045		$	5.79		6.50	$	264,454

Summary Information about Options Outstanding

The following table summarizes information about options outstanding as of March 31, 2019:

	Options Outstanding						Options Exercisable
Range of Exercise Prices	Number Outstanding		Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$4.36 - $7.20		468,810		7.03	$	4.46		413,253	$	4.47
$7.50 - $11.30		85,198		4.89		9.74		85,198		9.74
$12.00 - $19.70		17,244		3.26		13.60		17,244		13.60
$21.70 - $24.20		4,350		2.43		23.27		4,350		23.27
$4.36 - $24.20		575,602						520,045

Summary of RSU Activity

The following is a summary of RSU activity for the three months ended March 31, 2019:

	Number of RSUs			Weighted Average Fair Value
Unvested at December 31, 2018		1,367,630		$	3.81
Granted		226,000			5.21
Vested		(152,527	)		3.60
Forfeited		(10,871	)		3.45
Unvested at March 31, 2019		1,430,232		$	4.05
Shares vested but not released		425,966		$	3.39

Stock-Based Compensation Expense Related to Stock Options and RSUs

The following table illustrates all employee stock-based compensation expense related to stock options and RSUs included in the condensed consolidated statements of operations for the three months ended March 31, 2019 and 2018 (in thousands):

	Three Months Ended
	March 31,
	2019		2018
Cost of revenue	$	29	$	19
Research and development		114		135
Selling and marketing		180		158
General and administrative		364		323
Total	$	687	$	635