Stockholders' Equity (Tables)
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6 Months Ended |
Jun. 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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(75,315
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0.75-58.95
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24.96
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Forfeited
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(35,316
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38.54-58.95
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44.45
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Expired
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—
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—
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—
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Outstanding as of June 30, 2019
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1,016,705
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0.75-83.30
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35.30
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3.34
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32.51
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Vested and exercisable as of June 30, 2019
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902,341
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0.75-83.30
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34.12
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3.27
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33.82
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Vested and expected to vest as of June 30, 2019
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1,009,324
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$0.75-$83.30
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$
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35.23
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3.34
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$
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32.59
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| Summary of Restricted Stock Activity |
Stock Awards activity for the six months ended June 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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49,892
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—
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49,892
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96.52
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Vested
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(17,690
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(4,366
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(22,056
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125.95
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Forfeited/canceled
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(6,632
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(1,239
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(7,871
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89.42
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Unvested restricted stock units outstanding as of June 30, 2019 (1)
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84,159
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3,134
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87,293
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$
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104.10
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Unvested and expected to vest restricted stock units outstanding as
of June 30, 2019
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82,866
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$
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103.77
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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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26,778
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40,166
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66,944
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106.97
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Vested
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(8,699
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(15,732
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(24,431
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114.89
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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 June 30, 2019 (1)
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47,923
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62,628
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110,551
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$
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112.23
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Unvested and expected to vest restricted stock awards outstanding as
of June 30, 2019
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66,529
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$
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112.65
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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 six months ended June 30, 2019 and June 30, 2018, respectively, 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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Stock option plan awards
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$
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776
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$
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1,548
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$
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1,923
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$
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3,500
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Restricted stock units and restricted stock awards
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791
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1,416
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3,048
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2,654
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Employee stock purchase plan
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212
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222
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394
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413
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Total stock-based compensation expense
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$
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1,779
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$
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3,186
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$
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5,365
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$
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6,567
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For the three and six months ended June 30, 2019 and June 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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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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Cost of revenue
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$
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199
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$
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259
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$
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484
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$
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532
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Research and development
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227
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330
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604
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661
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Sales and marketing
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336
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583
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1,026
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1,131
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General and administrative
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1,017
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2,014
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3,251
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4,243
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Total stock-based compensation expense
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$
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1,779
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$
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3,186
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$
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5,365
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$
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6,567
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