Stock Based Compensation (Tables)
|
6 Months Ended |
Jun. 30, 2019 |
|---|
| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |
|
| Summary of Stock Option Activity |
The following is a summary of the Company’s stock option activity during the six months ended June 30, 2019:
|
|
|
Number of
Options
|
|
|
Weighted
Average
Exercise
Price
|
|
|
Weighted
Average
Remaining
Life In
Years
|
|
|
Intrinsic
Value
|
|
|
Outstanding at January 1, 2019
|
|
|
656,494
|
|
|
$
|
5.57
|
|
|
|
4.6
|
|
|
$
|
252,887
|
|
|
Granted
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
Exercised
|
|
|
(80,201
|
)
|
|
|
4.99
|
|
|
|
–
|
|
|
|
–
|
|
|
Forfeited
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
Outstanding at June 30, 2019
|
|
|
576,293
|
|
|
$
|
5.65
|
|
|
|
4.8
|
|
|
$
|
104,601
|
|
|
Exercisable at January 1, 2019
|
|
|
656,494
|
|
|
$
|
5.57
|
|
|
|
4.6
|
|
|
$
|
252,887
|
|
|
Vested
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
Exercised
|
|
|
(80,201
|
)
|
|
|
4.99
|
|
|
|
–
|
|
|
|
–
|
|
|
Forfeited
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
|
–
|
|
|
Exercisable at June 30, 2019
|
|
|
576,293
|
|
|
$
|
5.65
|
|
|
|
4.8
|
|
|
$
|
104,601
|
|
|
| Schedule of Restricted Stock Units Activity |
A summary of the activity related to RSUs for the six months ended June 30, 2019 is presented below:
|
|
|
Total
|
|
|
Weighted
Average
Grant
Date Fair
Value
|
|
|
Outstanding at January 1, 2019
|
|
|
2,469,174
|
|
|
$
|
15.07
|
|
|
RSUs granted
|
|
|
495,237
|
|
|
$
|
6.15
|
|
|
RSUs forfeited
|
|
|
(391,130
|
)
|
|
$
|
14.99
|
|
|
RSUs vested
|
|
|
(623,743
|
)
|
|
$
|
14.94
|
|
|
Outstanding at June 30, 2019
|
|
|
1,949,538
|
|
|
$
|
12.86
|
|
|
| Summary of Fair Values of Stock Options Granted |
The fair values of stock options granted were estimated using the following assumptions:
|
|
|
Six Months Ended
June 30, 2019
|
|
|
Six Months Ended
June 30, 2018
|
|
|
Stock price
|
|
$
|
5.79
|
|
|
$
|
22.34
|
|
|
Dividend yield
|
|
|
0
|
%
|
|
|
0
|
%
|
|
Expected volatility
|
|
|
96
|
%
|
|
|
177
|
%
|
|
Risk-free interest rate
|
|
|
2.51
|
%
|
|
|
1.61
|
%
|
|
Expected life
|
|
6 months
|
|
|
6 months
|
|
|
| Summary of Stock-based Compensation Costs Recognized |
The following tables summarize total stock-based compensation costs recognized for the three and six months ended June 30, 2019 and 2018:
|
|
|
Three Months Ended June 30,
|
|
|
Six Months Ended June 30,
|
|
|
|
|
|
2019
|
|
|
2018
|
|
|
2019
|
|
|
2018
|
|
|
|
RSUs
|
|
|
2,675,184
|
|
|
$
|
3,884,725
|
|
|
|
5,758,751
|
|
|
$
|
8,136,686
|
|
|
|
PSUs
|
|
|
–
|
|
|
|
204,954
|
|
|
|
–
|
|
|
|
407,656
|
|
|
|
ESPP
|
|
|
122,749
|
|
|
|
253,201
|
|
|
|
210,574
|
|
|
|
407,746
|
|
|
|
Total
|
|
$
|
2,797,933
|
|
|
$
|
4,342,880
|
|
|
$
|
5,969,325
|
|
|
$
|
8,952,088
|
|
|
|
| Summary of Stock-based Compensation Reflected within Statements of Operations |
The total amount of stock-based compensation was reflected within the statements of operations as:
|
|
|
Three Months Ended June 30,
|
|
|
Six Months Ended June 30,
|
|
|
|
|
|
2019
|
|
|
2018
|
|
|
2019
|
|
|
2018
|
|
|
|
Research and development
|
|
$
|
1,361,225
|
|
|
$
|
2,483,693
|
|
|
$
|
3,017,778
|
|
|
$
|
5,542,223
|
|
|
|
Sales and marketing
|
|
|
343,945
|
|
|
|
388,533
|
|
|
|
720,993
|
|
|
|
669,891
|
|
|
|
General and administrative
|
|
|
1,092,763
|
|
|
|
1,470,654
|
|
|
|
2,230,554
|
|
|
|
2,739,974
|
|
|
|
Total
|
|
$
|
2,797,933
|
|
|
$
|
4,342,880
|
|
|
$
|
5,969,325
|
|
|
$
|
8,952,088
|
|
|
|