Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Valuation Assumptions

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing formula that uses assumptions noted in the following table. Expected volatilities and risk-free interest rates are based upon the expected life of the grant.

	Nine months ended
Assumptions	September 30, 2017		September 30, 2016
Expected dividends	—	%	—	%
Risk-free rate	1.55	%	1.11	%
Expected volatility	58.0% - 69.7%		68.0% - 70.4%
Expected term (in years)	3.2 - 3.3		3.1 - 3.3

Schedule of Stock Option Activity

A summary of option activity under the Director Plan, the 2009 Plan and the 2016 Plan as of September 30, 2017 and changes during the period are presented below:

	Number of Options		Weighted Average Exercise Price
Outstanding as of January 1, 2017	4,105,369		$	4.76
Issued	558,345		7.35
Exercised	(171,566	)	1.56
Forfeited	(173,971	)	7.44
Expired	—		—
Outstanding as of September 30, 2017	4,318,177		$	5.11
Exercisable as of September 30, 2017	2,981,134		$	3.91

Schedule of Stock Options Outstanding and Exercisable

The following table summarizes information regarding options outstanding and exercisable at September 30, 2017:

Outstanding:

	Stock Options	Weighted Average		Weighted Average Remaining
Range of Exercise Prices	Outstanding	Exercise Price		Contractual Life
$0.79 - $1.00	25,000	$	0.79	2.26
$1.01 - $1.50	1,721,000	1.06		4.39
$1.51 - $10.67	2,572,177	7.87		8.01
Total	4,318,177	$	5.11	6.53

Exercisable:

	Stock Options	Weighted Average
Range of Exercise Prices	Exercisable	Exercise Price
$0.79 - $1.00	25,000	$	0.79
$1.01 - $1.50	1,721,000	1.06
$1.51 - $10.67	1,235,134	7.93
Total	2,981,134	$	3.91

Schedule of Nonvested Restricted Stock Units Activity

The following table summarizes the number of unvested RSUs and their weighted average exercise price for the nine months ended September 30, 2017.

	Number of RSUs		Weighted Average Exercise Price
Non-vested balance at January 1, 2017	179,900		$	9.35
Changes during the period:
Shares granted	93,468		7.26
Shares vested	(71,941	)	9.82
Shares forfeited	(4,465	)	7.09
Non-vested balance at September 30, 2017	196,962		$	8.23