Stockholders' Equity (Tables)
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9 Months Ended |
Sep. 30, 2019 |
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| Equity [Abstract] |
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| Summary of Stock Options Activity |
The activity for stock options under the Company’s stock plans is as follows:
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Remaining
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weighted-
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Weighted-
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average
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Per share
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average
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contractual
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average
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Price per
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exercise
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terms
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intrinsic
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Options
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share
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price
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(in years)
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value
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Outstanding as of December 31, 2018
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1,127,336
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$0.75-$83.30
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$
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34.89
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3.84
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$
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89.28
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Granted
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—
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—
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—
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Exercised
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(82,053
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0.75-58.95
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24.80
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Forfeited
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(37,161
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38.54-58.95
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44.58
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Expired
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—
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—
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—
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Outstanding as of September 30, 2019
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1,008,122
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0.75-83.30
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35.36
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3.09
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14.85
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Vested and exercisable as of September 30, 2019
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926,026
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0.75-83.30
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34.54
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3.05
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15.85
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Vested and expected to vest as of September 30, 2019
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1,002,824
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$0.75-$83.30
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$
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35.31
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3.09
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$
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14.91
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| Summary of Restricted Stock Activity |
Stock Awards activity for the nine months ended September 30, 2019 are summarized below:
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Weighted-
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average
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grant
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Performance
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date fair
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and
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value
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Restricted stock units
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Time-based
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time-based
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Total
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per share
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Unvested restricted stock units outstanding as of December 31, 2018
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58,589
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8,739
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67,328
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$
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115.16
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Granted
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80,450
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—
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80,450
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76.16
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Vested
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(21,257
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(4,366
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(25,623
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125.04
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Forfeited/canceled
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(10,935
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(1,239
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(12,174
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100.36
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Unvested restricted stock units outstanding as of September 30, 2019 (1)
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106,847
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3,134
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109,981
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$
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85.97
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Unvested and expected to vest restricted stock units outstanding as
of September 30, 2019
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101,117
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$
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85.75
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Weighted-
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average
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grant
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Performance
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date fair
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and
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value
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Restricted stock awards
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Time-based
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time-based
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Total
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per share
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Unvested restricted stock awards outstanding as of December 31, 2018
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36,937
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47,821
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84,758
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$
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115.80
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Granted
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51,234
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40,166
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91,400
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86.89
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Vested
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(10,986
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(15,732
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(26,718
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114.17
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Forfeited/canceled
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(7,093
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(9,627
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(16,720
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109.11
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Unvested restricted stock awards outstanding as of September 30, 2019 (1)
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70,092
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62,628
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132,720
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$
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97.34
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Unvested and expected to vest restricted stock awards outstanding as
of September 30, 2019
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78,627
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$
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92.43
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(1)
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Outstanding restricted stock units and restricted stock awards are based on the maximum payout of the targeted number of shares.
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| Summary of Stock-based Compensation Expense |
Stock-based compensation
Stock-based compensation expense recognized for the three and nine months ended September 30, 2019 and September 30, 2018, respectively, was as follows:
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Three months ended
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Nine months ended
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September 30,
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September 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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Stock option plan awards
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$
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590
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$
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1,348
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$
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2,513
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$
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4,847
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Restricted stock units and restricted stock awards
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834
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1,679
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3,882
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4,334
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Employee stock purchase plan
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141
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189
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535
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602
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Total stock-based compensation expense
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$
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1,565
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$
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3,216
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$
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6,930
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$
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9,783
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For the three and nine months ended September 30, 2019 and September 30, 2018, respectively, stock-based compensation expense recognized under ASC 718, included in cost of revenue, research and development expense, sales and marketing expense, and general and administrative expense was as follows:
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Three months ended
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Nine months ended
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September 30,
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September 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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Cost of revenue
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$
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172
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$
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187
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$
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656
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$
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719
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Research and development
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221
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348
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825
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1,010
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Sales and marketing
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263
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630
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1,289
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1,761
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General and administrative
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909
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2,051
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4,160
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6,293
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Total stock-based compensation expense
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$
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1,565
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$
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3,216
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$
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6,930
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$
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9,783
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