Stock Plans (Tables)
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6 Months Ended |
Jun. 30, 2019 |
|---|
| Schedule of Stock-based Compensation Expense |
The Company’s stock-based compensation expense recognized for the periods presented was as follows:
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Three Months Ended
|
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Six Months Ended
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June 30,
|
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June 30,
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2019
|
|
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2018
|
|
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2019
|
|
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2018
|
|
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Stock-based compensation expense by type of award:
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|
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|
|
|
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|
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Restricted stock units
|
|
$
|
299
|
|
|
$
|
99
|
|
|
$
|
497
|
|
|
$
|
147
|
|
|
Restricted stock awards
|
|
|
96
|
|
|
|
135
|
|
|
|
256
|
|
|
|
353
|
|
|
Machine Box contingent common stock issuances
|
|
|
523
|
|
|
|
—
|
|
|
|
1,227
|
|
|
|
—
|
|
|
Performance-based stock options
|
|
|
2,020
|
|
|
|
53
|
|
|
|
3,956
|
|
|
|
53
|
|
|
Stock options
|
|
|
2,703
|
|
|
|
2,246
|
|
|
|
5,060
|
|
|
|
4,282
|
|
|
Employee stock purchase plan
|
|
|
137
|
|
|
|
118
|
|
|
|
289
|
|
|
|
290
|
|
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Total
|
|
$
|
5,778
|
|
|
$
|
2,651
|
|
|
$
|
11,285
|
|
|
$
|
5,125
|
|
|
|
|
Three Months Ended
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Six Months Ended
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June 30,
|
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June 30,
|
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2019
|
|
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2018
|
|
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2019
|
|
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2018
|
|
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Stock-based compensation expense by operating expense grouping:
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|
|
|
|
|
|
|
|
|
|
|
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|
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Sales and marketing
|
|
$
|
271
|
|
|
$
|
248
|
|
|
$
|
514
|
|
|
$
|
568
|
|
|
Research and development
|
|
|
900
|
|
|
|
266
|
|
|
|
1,984
|
|
|
|
507
|
|
|
General and administrative
|
|
|
4,607
|
|
|
|
2,137
|
|
|
|
8,787
|
|
|
|
4,050
|
|
|
|
|
$
|
5,778
|
|
|
$
|
2,651
|
|
|
$
|
11,285
|
|
|
$
|
5,125
|
|
|
| Schedule of Restricted Stock Award Activity |
The Company’s restricted stock award activity for the six months ended June 30, 2019 was as follows:
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Weighted
|
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|
|
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|
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Average Grant
|
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Shares
|
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Date Fair Value
|
|
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Unvested at December 31, 2018
|
|
|
72,208
|
|
|
$
|
7.26
|
|
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Vested
|
|
|
(31,245
|
)
|
|
$
|
6.95
|
|
|
Unvested at June 30, 2019
|
|
|
40,963
|
|
|
$
|
7.50
|
|
|
| Schedule of Restricted Stock Unit Activity |
The Company’s restricted stock unit activity for the six months ended June 30, 2019 was as follows:
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Weighted
|
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|
|
|
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Average Grant
|
|
|
|
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Shares
|
|
|
Date Fair Value
|
|
|
Unvested at December 31, 2018
|
|
|
49,143
|
|
|
$
|
12.57
|
|
|
Granted
|
|
|
150,211
|
|
|
$
|
7.28
|
|
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Forfeited
|
|
|
(1,000
|
)
|
|
$
|
8.81
|
|
|
Vested
|
|
|
(35,609
|
)
|
|
$
|
13.99
|
|
|
Unvested at June 30, 2019
|
|
|
162,745
|
|
|
$
|
7.40
|
|
|
| Schedule of Stock Option Activity |
The activity during the six months ended June 30, 2019 related to all other stock options was as follows:
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Weighted-Average
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Remaining
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Aggregate
|
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Exercise
|
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Contractual
|
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Intrinsic
|
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Options
|
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Price
|
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Term
|
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Value
|
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Outstanding at December 31, 2018
|
|
|
5,154,691
|
|
|
$
|
13.78
|
|
|
|
|
|
|
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|
Granted
|
|
|
555,346
|
|
|
$
|
5.98
|
|
|
|
|
|
|
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Exercised
|
|
|
(47,099
|
)
|
|
$
|
2.56
|
|
|
|
|
|
|
|
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Forfeited
|
|
|
(183,892
|
)
|
|
$
|
12.45
|
|
|
|
|
|
|
|
|
Expired
|
|
|
(58,459
|
)
|
|
$
|
13.09
|
|
|
|
|
|
|
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Outstanding at June 30, 2019
|
|
|
5,420,587
|
|
|
$
|
13.13
|
|
|
8.08 years
|
|
$
|
3,368
|
|
|
Exercisable at June 30, 2019
|
|
|
3,269,820
|
|
|
$
|
13.94
|
|
|
7.65 years
|
|
$
|
1,811
|
|
|
| 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 six months ended June 30, 2019 are set forth in the table below:
|
Expected term (in years)
|
|
0.5 - 2.0
|
|
|
Expected volatility
|
|
51% - 71%
|
|
|
Risk-free interest rate
|
|
1.3% - 2.5%
|
|
|
Expected dividend yield
|
|
|
—
|
|
|
| Timebased Stock Option [Member] |
|
| Schedule of Fair Value Assumptions |
The following assumptions were used to compute the grant date fair values of the Time-Based Options granted during the six months ended June 30, 2019:
|
Expected term (in years)
|
|
6.0 - 6.1
|
|
|
Expected volatility
|
|
66% - 68%
|
|
|
Risk-free interest rate
|
|
1.8% - 2.5%
|
|
|
Expected dividend yield
|
|
|
—
|
|
|
| Performance-based Stock Options [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 Performance Options granted during the six months ended June 30, 2019:
|
Estimated volatility
|
|
|
65
|
%
|
|
Risk-free interest rate
|
|
|
2.7
|
%
|
|
Dividend yield
|
|
|
—
|
%
|
|
Cost of equity
|
|
|
14
|
%
|
|
| Schedule of Stock Option Activity |
The activity during the six months ended June 30, 2019 related to stock options that are subject to performance-based vesting conditions tied to the future achievement of stock price goals by the Company was as follows:
|
|
|
|
|
|
|
Weighted-Average
|
|
|
|
|
|
|
|
|
|
|
|
|
Remaining
|
|
|
Aggregate
|
|
|
|
|
|
|
|
|
Exercise
|
|
|
Contractual
|
|
|
Intrinsic
|
|
|
|
|
Options
|
|
|
Price
|
|
|
Term
|
|
|
Value
|
|
|
Outstanding at December 31, 2018
|
|
|
3,167,325
|
|
|
$
|
21.25
|
|
|
|
|
|
|
|
|
|
|
Granted
|
|
|
1,545,849
|
|
|
$
|
5.74
|
|
|
|
|
|
|
|
|
|
|
Forfeited
|
|
|
(102,648
|
)
|
|
$
|
5.67
|
|
|
|
|
|
|
|
|
|
|
Outstanding at June 30, 2019
|
|
|
4,610,526
|
|
|
$
|
16.40
|
|
|
9.11 years
|
|
|
$
|
3,771
|
|
|
Exercisable at June 30, 2019
|
|
|
—
|
|
|
$
|
—
|
|
|
|
—
|
|
|
$
|
—
|
|
|