Stockholders' Equity (Tables)
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6 Months Ended |
Jun. 30, 2018 |
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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, 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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(276,016
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0.60-58.95
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23.61
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Forfeited
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(625
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24.52
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24.52
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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, 2018
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1,559,785
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$0.60-$83.30
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$
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32.04
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4.24
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$
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154.29
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Vested and exercisable as of June 30, 2018
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1,128,065
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$0.60-$83.30
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$
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27.97
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4.12
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$
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158.36
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Vested and expected to vest as of June 30, 2018
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1,531,385
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$0.60-$83.30
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$
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31.85
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4.23
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$
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154.48
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| Summary of Restricted Stock Activity |
Stock Awards activity for the six months ended June 30, 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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28,273
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—
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28,273
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137.92
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Vested
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(2,295
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(4,370
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(6,665
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86.70
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Forfeited/canceled
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(1,452
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—
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(1,452
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104.81
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Unvested restricted stock units outstanding as of June 30, 2018 (1)
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66,554
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8,739
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75,293
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$
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108.04
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Unvested and expected to vest restricted stock units outstanding as
of June 30, 2018
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69,947
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$
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108.69
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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 June 30, 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 June 30, 2018
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69,176
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$
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108.43
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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 months and six months ended June 30, 2018 and June 30, 2017 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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2018
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2017
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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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1,548
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$
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2,055
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$
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3,500
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$
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3,799
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Restricted stock units and restricted stock awards
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1,416
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24
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2,654
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48
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Employee stock purchase plan
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222
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137
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413
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260
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Total stock-based compensation expense
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$
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3,186
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$
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2,216
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$
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6,567
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$
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4,107
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For the three months and six months ended June 30, 2018 and June 30, 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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Six months ended
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June 30,
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June 30,
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2018
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2017
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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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259
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$
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212
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$
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532
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$
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403
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Research and development
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330
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250
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661
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473
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Sales and marketing
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583
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347
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1,131
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662
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General and administrative
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2,014
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1,407
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4,243
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2,569
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Total stock-based compensation expense
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$
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3,186
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$
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2,216
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$
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6,567
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$
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4,107
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