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Stock Incentive Plan (Tables)
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12 Months Ended |
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Dec. 31, 2014
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |
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| Summary of ESPP Stock Plan Activity |
The activity for the 2014 ESPP Stock Plan is as follows:
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First Offering
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Second Offering
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Period
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Period*
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Employee accumulated payroll deductions
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414
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250
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Total Shares Purchased
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30,358
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—
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Payroll deductions used to purchase shares
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413
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—
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Transfer to next offering period
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1
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—
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FMV at enrollment date
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$
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16.00
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$
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21.69
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FMV at purchase date
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$
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21.69
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—
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Purchase price
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$
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13.60
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—
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*Offering period ends March 2, 2015
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| Summary of Stock Options Activity |
The activity for stock options under our option plans is as follows:
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Options
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Price per share
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Weighted-average exercise price
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Remaining weighted-average contractual terms (in years)
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Per share average intrinsic value
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Outstanding as of December 31, 2012
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1,646,223
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$0.60-$8.70
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$
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1.06
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6.99
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$
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0.41
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Granted
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716,326
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$1.17-$8.37
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$
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3.95
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Exercised
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(8,874
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)
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$0.60-$8.70
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$
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1.35
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Forfeited
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(23,106
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)
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$0.60-$8.37
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$
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2.46
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Expired
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(1,894
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)
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$0.60-$8.70
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$
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1.53
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Outstanding as of December 31, 2013
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2,328,675
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$0.60-$8.70
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$
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1.94
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7.04
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$
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10.23
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Vested and exercisable at December 31, 2013
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1,524,325
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$0.60-$8.70
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$
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1.16
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5.95
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$
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11.01
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Vested and expected to vest, at December 31, 2013
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2,226,738
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$0.60-$8.70
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$
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1.88
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6.95
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$
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10.29
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Outstanding as of December 31, 2013
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2,328,675
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$0.60-$8.70
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$
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1.94
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Granted
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754,916
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$16.62-$24.52
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$
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17.81
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Exercised
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(736,519
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)
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$0.60-$16.62
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$
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1.28
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Forfeited
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(80,640
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)
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$0.60-$16.62
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$
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5.81
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Expired
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(4,799
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)
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$0.60-$8.37
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$
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1.09
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Outstanding as of December 31, 2014
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2,261,633
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$0.60-$24.52
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$
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7.31
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6.43
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$
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24.06
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Vested and exercisable at December 31, 2014
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1,100,539
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$0.60-$18.93
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$
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2.02
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5.73
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$
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29.35
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Vested and expected to vest, at December 31, 2014
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2,144,974
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$0.60-$24.52
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$
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7.19
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6.38
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$
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24.18
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| Summary of Stock Options Outstanding |
The following table summarizes information about stock options outstanding at December 31, 2014:
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Outstanding
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Exercisable
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Weighted-
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Weighted-
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average
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average
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life
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exercise
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exercise
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Exercise price per share
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Shares
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(years)
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price
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Shares
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price
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$
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0.60
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515,582
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5.00
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$
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0.60
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515,582
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$
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0.60
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$
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0.75
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84,724
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6.75
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0.75
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66,276
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0.75
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$
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0.81
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221,593
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7.27
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0.81
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143,955
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0.81
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$
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1.17
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293,436
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8.15
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1.17
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109,748
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1.17
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$2.40-$6.00
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148,490
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3.22
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2.42
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148,490
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2.42
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$
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8.37
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257,471
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8.77
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8.37
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73,035
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8.37
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$
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8.70
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9,962
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1.12
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8.70
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9,962
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8.70
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$
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16.62
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608,153
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6.25
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16.62
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33,121
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16.62
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$
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18.93
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12,222
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6.62
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18.93
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370
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18.93
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$
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24.52
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110,000
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6.89
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24.52
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—
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—
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2,261,633
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6.43
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$
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7.31
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1,100,539
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$
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2.02
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The following table summarizes information about stock options outstanding at December 31, 2013:
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Outstanding
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Exercisable
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|
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Weighted-
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|
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|
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Weighted-
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|
|
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average
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average
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life
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exercise
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|
exercise
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Exercise price per share
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Shares
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(years)
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price
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Shares
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price
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$
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0.60
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920,687
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5.96
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$
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0.60
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916,917
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$
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0.60
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$
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0.75
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128,845
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7.75
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0.75
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76,466
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0.75
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$
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0.81
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244,979
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8.26
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0.81
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102,329
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0.81
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$
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1.17
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427,805
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9.09
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1.17
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82,249
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1.17
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$
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2.10
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|
66
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0.09
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|
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2.10
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66
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2.10
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$
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2.40
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316,089
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4.13
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2.40
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316,089
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2.40
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$
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4.24
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7,461
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|
0.52
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4.50
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7,461
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4.24
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$
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8.37
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271,829
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9.77
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|
|
8.37
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11,834
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|
|
8.37
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$
|
8.70
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10,914
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|
|
|
2.19
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|
|
8.70
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|
|
10,914
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|
|
|
8.70
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|
|
|
|
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2,328,675
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|
7.04
|
|
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$
|
1.94
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|
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1,524,325
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$
|
1.16
|
|
|
| Assumptions Used to Estimate Fair Value of Employee Options |
The value of employee options was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions used:
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2014
|
|
2013
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|
2012
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Expected term (years)
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4.02-6.99
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5.26-6.03
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5.51-6.07
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Risk free interest rate
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1.32-2.02%
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1.08-1.76%
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0.73-1.33%
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Expected dividend yield
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None
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None
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None
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Volatility
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42.15-52.73%
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50.1-52.77%
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48.95-50.52%
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|