Stockholders' Equity (Tables)
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3 Months Ended |
Mar. 31, 2018 |
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, 2017
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1,836,426
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$0.60-$83.30
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$
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30.77
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4.58
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$
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88.31
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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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(169,594
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0.60-58.95
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26.29
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Forfeited
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—
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—
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—
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Expired
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—
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—
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—
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Outstanding as of March 31, 2018
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1,666,832
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$0.60-$83.30
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$
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31.23
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4.45
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$
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91.61
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Vested and exercisable as of March 31, 2018
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1,134,940
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$0.60-$83.30
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$
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25.82
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4.31
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$
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97.02
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Vested and expected to vest as of March 31, 2018
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1,631,773
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$0.60-$83.30
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$
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30.98
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4.44
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$
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91.86
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Summary of Restricted Stock Activity |
Stock Awards activity for the three months ended March 31, 2018, is 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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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, 2017
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42,028
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13,109
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55,137
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$
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90.05
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Granted
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20,049
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—
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20,049
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122.00
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Vested
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(1,836
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(4,370
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(6,206
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87.38
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Forfeited/canceled
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(546
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—
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(546
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91.52
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Unvested restricted stock units outstanding as of March 31, 2018 (1)
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59,695
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8,739
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68,434
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$
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99.64
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Unvested and expected to vest restricted stock units outstanding as
of March 31, 2018
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63,143
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$
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99.79
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Unvested restricted stock awards outstanding as of December 31, 2017
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20,789
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20,785
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41,574
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$
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91.52
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Granted
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21,222
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31,830
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53,052
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122.00
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Vested
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—
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(6,928
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(6,928
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91.52
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Forfeited/canceled
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—
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—
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—
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—
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Unvested restricted stock awards outstanding as of March 31, 2018 (1)
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42,011
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45,687
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87,698
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$
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108.30
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Unvested and expected to vest restricted stock awards outstanding as
of March 31, 2018
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67,432
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$
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108.07
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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 months ended March 31, 2018 and March 31, 2017 was as follows:
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Three months ended
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March 31,
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2018
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2017
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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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1,951
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$
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1,744
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Restricted stock units and restricted stock awards
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1,239
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24
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Employee stock purchase plan
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191
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123
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Total stock-based compensation expense
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$
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3,381
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$
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1,891
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For the three months ended March 31, 2018 and March 31, 2017, 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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March 31,
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2018
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2017
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Cost of revenue
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$
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273
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$
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191
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Research and development
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331
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223
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Sales and marketing
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548
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315
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General and administrative
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2,229
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1,162
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Total stock-based compensation expense
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$
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3,381
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$
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1,891
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