STOCK-BASED COMPENSATION (Tables)

9 Months Ended

Sep. 30, 2018

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

Schedule of stock options and awards

	September 30, 2018
Common stock shares available for grant	1,714,531
Standard and market condition stock options outstanding	2,322,517
Restricted stock awards outstanding	62,556
RSUs outstanding	1,090,938

Schedule of employee stock purchase plan

The intrinsic value listed below is calculated as the difference between the market value on the date of purchase and the purchase price of the shares.

	Nine Months Ended September 30, 2018
Shares purchased under ESPP	26,689
Average price of shares purchased under ESPP	$	8.17
Intrinsic value of shares purchased under ESPP	$	106,000

Schedule of standard and market-based stock options activity

The following table sets forth the summary of activity with respect to standard stock options granted under the Company’s stock option plans for the nine months ended September 30, 2018:

	Nine Months Ended September 30, 2018
Beginning outstanding balance	3,277,991
Granted	207,500
Exercised	(1,326,718		)
Forfeited	(50,140		)
Expired	(58,197		)
Ending outstanding balance	2,050,436
Aggregate intrinsic value of options exercised	$	7,905,000
Weighted average fair value of options granted	$	5.82

Schedule of information regarding standard and market condition based stock options outstanding

Information regarding these standard stock options outstanding at September 30, 2018 is summarized below:

	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (years)	Aggregate Intrinsic Value (in millions)
September 30, 2018
Options outstanding	2,050,436	$	9.31	2.97	$	3.3
Options vested and expected to vest using estimated forfeiture rates	1,956,894	9.27		2.82	3.1
Options exercisable	1,511,605	$	9.11	2.00	$	2.5

Schedule of restricted stock units activity

RSU activity for the nine months ended September 30, 2018 was as follows:

	Nine Months Ended September 30, 2018
Beginning outstanding balance	508,880
Awarded	922,443
Released	(178,447		)
Forfeited	(161,938		)
Ending outstanding balance	1,090,938
Weighted average fair value on grant date of RSUs	$	11.83
Total fair value of RSUs released	$	2,133,000

Schedule of information regarding restricted stock units outstanding

Information regarding RSUs outstanding at September 30, 2018 is summarized below:

	Number of Shares	Weighted Average Remaining Contractual Life (years)	Aggregate Intrinsic Value (in millions)
September 30, 2018
RSUs outstanding	1,090,938	0.90	$	11.5
RSUs vested and expected to vest using estimated forfeiture rates	915,934	0.80	$	9.7

Schedule of restricted stock awards activity

Restricted stock award activity for the nine months ended September 30, 2018 was as follows:

	Nine Months Ended September 30, 2018
Beginning outstanding balance	44,538
Awarded	62,556
Released	(44,538		)
Forfeited	—
Ending outstanding balance	62,556
Weighted average grant date fair value of restricted stock awarded	$	13.32
Total fair value of restricted stock awards released	$	673,000

Schedule of stock options, market condition based stock options and employee stock purchase plan, valuation assumptions

The assumptions used to value option grants under the Company’s stock plans were as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2018		2017		2018		2017
Standard Stock Options
Expected life (in years)	4.5		4.6		4.4		4.5
Volatility	55	%	53	%	55	%	53	%
Interest rate	2.7	%	1.7	%	2.5	%	1.7	%
Dividend yield	N/A		N/A		N/A		N/A

	Three Months Ended September 30,		Nine Months Ended September 30,
	2018	2017	2018		2017
Market Condition Based Stock Options
Expected life (in years)	N/A	N/A	7.0		7.0
Volatility	N/A	N/A	55	%	55	%
Interest rate	N/A	N/A	2.0	%	2.0	%
Dividend yield	N/A	N/A	N/A		N/A

	Three Months Ended September 30,				Nine Months Ended September 30,
	2018		2017		2018		2017
Employee Stock Purchase Plan
Expected life (in years)	0.5		0.5		0.5		0.5
Volatility	39	%	46	%	58	%	48	%
Interest rate	2.2	%	1.1	%	1.9	%	0.9	%
Dividend yield	N/A		N/A		N/A		N/A

Schedule of stock-based compensation

Total stock-based compensation recognized in the condensed consolidated statements of operations and comprehensive income (loss) is as follows:

(in thousands)	Three Months Ended September 30,				Nine Months Ended September 30,
	2018		2017		2018		2017
Statement of Operations Classifications
Sales and marketing	$	377	$	317	$	675	$	808
Research and development	561		231		1,382		780
General and administrative	1,576		790		4,209		2,485
Total	$	2,514	$	1,338	$	6,266	$	4,073