Stock Plans (Tables)
|
12 Months Ended |
Dec. 31, 2018 |
|---|
| Summary of Fair Value Per Share Determined for Each of Three Equal Tranches of Award |
The fair value per share was determined for each of the three equal tranches of each award and is presented in the table below:
|
Tranche 1
|
|
$
|
9.22
|
|
|
Tranche 2
|
|
$
|
10.05
|
|
|
Tranche 3
|
|
$
|
9.50
|
|
|
| Schedule of Stock-based Compensation Expense |
The stock-based compensation expense by type of award and by operating expense grouping are presented below:
|
|
|
Year Ended
|
|
|
|
|
December 31,
|
|
|
|
|
2018
|
|
|
2017
|
|
|
Stock-based compensation expense by type of award:
|
|
|
|
|
|
|
|
|
|
Restricted stock units
|
|
$
|
427
|
|
|
$
|
327
|
|
|
Restricted stock awards
|
|
|
463
|
|
|
|
891
|
|
|
Common stock awards
|
|
|
—
|
|
|
|
375
|
|
|
Performance-based stock options under the 2018 Plan
|
|
|
3,799
|
|
|
|
—
|
|
|
Stock options
|
|
|
10,050
|
|
|
|
14,391
|
|
|
Employee stock purchase plan
|
|
|
754
|
|
|
|
105
|
|
|
Total
|
|
$
|
15,493
|
|
|
$
|
16,089
|
|
|
|
|
|
|
|
|
|
|
|
|
Stock-based compensation expense by operating expense grouping:
|
|
|
|
|
|
|
|
|
|
Sales and marketing
|
|
$
|
1,018
|
|
|
$
|
438
|
|
|
Research and development
|
|
|
2,278
|
|
|
|
464
|
|
|
General and administrative
|
|
|
12,197
|
|
|
|
15,187
|
|
|
|
|
$
|
15,493
|
|
|
$
|
16,089
|
|
|
| Schedule of Restricted Stock Activity |
The Company’s restricted stock activity for the year ended December 31, 2018 was as follows:
|
|
|
|
|
|
|
Weighted
|
|
|
|
|
|
|
|
|
Average Grant
|
|
|
|
|
Shares
|
|
|
Date Fair Value
|
|
|
Unvested at December 31, 2017
|
|
|
147,456
|
|
|
$
|
6.30
|
|
|
Forfeited
|
|
|
(1,975
|
)
|
|
$
|
7.50
|
|
|
Vested
|
|
|
(73,273
|
)
|
|
$
|
5.32
|
|
|
Unvested at December 31, 2018
|
|
|
72,208
|
|
|
$
|
7.26
|
|
|
| Schedule of Restricted Stock Unit Activity |
The Company’s restricted stock units activity for the year ended December 31, 2018 was as follows:
|
|
|
|
|
|
|
Weighted
|
|
|
|
|
|
|
|
|
Average Grant
|
|
|
|
|
Shares
|
|
|
Date Fair Value
|
|
|
Unvested at December 31, 2017
|
|
|
35,576
|
|
|
$
|
14.76
|
|
|
Granted
|
|
|
69,198
|
|
|
$
|
13.46
|
|
|
Forfeited
|
|
|
(8,918
|
)
|
|
$
|
16.82
|
|
|
Vested
|
|
|
(46,713
|
)
|
|
$
|
14.74
|
|
|
Unvested at December 31, 2018
|
|
|
49,143
|
|
|
$
|
12.57
|
|
|
| Employee Stock Purchase Plan [Member] |
|
| Summary of Fair Value Assumptions of Stock Purchase Plan |
The assumptions used in calculating the fair values of purchase rights granted under the ESPP during the year ended December 31, 2018 and 2017 are set forth in the table below:
|
|
|
Year Ended
|
|
|
Year Ended
|
|
|
|
|
December 31,
|
|
|
December 31,
|
|
|
|
|
2018
|
|
|
2017
|
|
|
Expected term (in years)
|
|
|
0.5
|
|
|
|
0.5
|
|
|
Expected volatility
|
|
50.5% - 53.0%
|
|
|
|
53
|
%
|
|
Risk-free interest rate
|
|
1.18% - 1.89%
|
|
|
|
1.15
|
%
|
|
Expected dividend yield
|
|
|
—
|
|
|
|
—
|
|
|
| 2014 Plan Stock Options/Stock Issuance Plan and 2017 Stock Incentive Plan [Member] |
|
| Schedule of Fair Value Assumptions |
The assumptions used in calculating the fair values of options granted during the years ended December 31, 2018 and 2017 are set forth in the table below:
|
|
|
Year Ended
|
|
|
Year Ended
|
|
|
|
|
December 31,
|
|
|
December 31,
|
|
|
|
|
2018
|
|
|
2017
|
|
|
Expected term (in years)
|
|
6.01 - 6.07
|
|
|
5.83 - 6.31
|
|
|
Expected volatility
|
|
53% - 69%
|
|
|
52% - 65%
|
|
|
Risk-free interest rate
|
|
2.63% - 3.08%
|
|
|
1.79% - 2.20%
|
|
|
Expected dividend yield
|
|
|
—
|
|
|
|
—
|
|
|
| Schedule of Stock Option Activity |
The activity related to stock options granted under the 2014 Plan and 2017 Plan for the year ended December 31, 2018 was as follows:
|
|
|
|
|
|
|
Weighted-Average
|
|
|
|
|
|
|
|
|
|
|
|
|
Remaining
|
|
Aggregate
|
|
|
|
|
|
|
|
|
Exercise
|
|
|
Contractual
|
|
Intrinsic
|
|
|
|
|
Options
|
|
|
Price
|
|
|
Term
|
|
Value
|
|
|
Outstanding at December 31, 2017
|
|
|
4,802,594
|
|
|
$
|
13.89
|
|
|
9.17 years
|
|
$
|
44,712
|
|
|
Granted
|
|
|
1,031,091
|
|
|
$
|
13.19
|
|
|
|
|
|
|
|
|
Exercised
|
|
|
(151,121
|
)
|
|
$
|
3.63
|
|
|
|
|
|
|
|
|
Forfeited
|
|
|
(516,419
|
)
|
|
$
|
16.56
|
|
|
|
|
|
|
|
|
Expired
|
|
|
(11,454
|
)
|
|
$
|
14.23
|
|
|
|
|
|
|
|
|
Outstanding at December 31, 2018
|
|
|
5,154,691
|
|
|
$
|
13.78
|
|
|
8.41 years
|
|
$
|
707
|
|
|
Exercisable at December 31, 2018
|
|
|
2,743,923
|
|
|
$
|
13.47
|
|
|
8.04 years
|
|
$
|
677
|
|
|
| 2018 Performance- Based Stock Incentive Plan [Member] |
|
| Summary of Fair Value Assumptions of Stock Purchase Plan |
The following assumptions were used in the Monte Carlo simulation model for computing the grant date fair values of the CEO Award and the President Award:
|
Grant date stock price
|
|
$
|
16.82
|
|
|
Dividend yield
|
|
|
—
|
%
|
|
Risk-free interest rate
|
|
|
2.85
|
%
|
|
Estimated volatility
|
|
|
73.0
|
%
|
|
| 2018 Performance- Based Stock Incentive Plan [Member] | Performance-based Stock Options [Member] |
|
| Schedule of Stock Option Activity |
The activity related to performance-based stock options granted under the 2018 Plan for the year ended December 31, 2018 was as follows:
|
|
|
|
|
|
|
Weighted-Average
|
|
|
|
|
|
|
|
|
|
|
|
|
Remaining
|
|
|
Aggregate
|
|
|
|
|
|
|
|
|
Exercise
|
|
|
Contractual
|
|
|
Intrinsic
|
|
|
|
|
Options
|
|
|
Price
|
|
|
Term
|
|
|
Value
|
|
|
Outstanding at December 31, 2017
|
|
|
—
|
|
|
$
|
—
|
|
|
|
—
|
|
|
$
|
—
|
|
|
Granted
|
|
|
3,167,325
|
|
|
$
|
21.25
|
|
|
|
|
|
|
|
|
|
|
Outstanding at December 31, 2018
|
|
|
3,167,325
|
|
|
$
|
21.25
|
|
|
9.35 years
|
|
|
$
|
—
|
|
|
Exercisable at December 31, 2018
|
|
|
—
|
|
|
$
|
—
|
|
|
|
—
|
|
|
$
|
—
|
|
|