v2.4.1.9

Stock incentive plans (Tables) | 12 Months Ended
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Dec. 31, 2014
Stock incentive plans |
Schedule of stock-based compensation expense |
|  | Years ended December 31, |
|  | 2014 |  | 2013 |  | 2012 |
Network operations |  | $ | 1,356 |  | $ | 888 |  | $ | 352 |
Development and technology |  |  | 600 |  |  | 380 |  |  | 352 |
Selling and marketing |  |  | 2,017 |  |  | 1,045 |  |  | 571 |
General and administrative |  |  | 3,191 |  |  | 2,193 |  |  | 1,460 |
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Total stock-based compensation expense |  | $ | 7,164 |  | $ | 4,506 |  | $ | 2,735 |
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Summary of stock option activity |
|  | Number of Options (000's) |  | Weighted Average Exercise Price |  | Weighted- Average Remaining Contract Life (years) |  | Aggregate Intrinsic Value |
Outstanding at December 31, 2011 |  |  | 6,601 |  | $ | 5.50 |  |  | 7.0 |  | $ | 30,996 |
Granted |  |  | 1,391 |  | $ | 8.29 |  |  |  |  |  |  |
Exercised |  |  | (1,899 | ) | $ | 1.36 |  |  |  |  |  |  |
Canceled/forfeited |  |  | (1,048 | ) | $ | 11.85 |  |  |  |  |  |  |
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Outstanding at December 31, 2012 |  |  | 5,045 |  | $ | 6.50 |  |  | 6.4 |  | $ | 14,742 |
Granted |  |  | 1,351 |  | $ | 6.73 |  |  |  |  |  |  |
Exercised |  |  | (461 | ) | $ | 1.33 |  |  |  |  |  |  |
Canceled/forfeited |  |  | (980 | ) | $ | 10.20 |  |  |  |  |  |  |
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Outstanding at December 31, 2013 |  |  | 4,955 |  | $ | 6.31 |  |  | 6.6 |  | $ | 9,535 |
Granted |  |  | 203 |  | $ | 5.99 |  |  |  |  |  |  |
Exercised |  |  | (458 | ) | $ | 2.53 |  |  |  |  |  |  |
Canceled/forfeited |  |  | (359 | ) | $ | 7.53 |  |  |  |  |  |  |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Outstanding at December 31, 2014 |  |  | 4,341 |  | $ | 6.60 |  |  | 5.8 |  | $ | 11,017 |
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Vested, exercisable and expected to vest at December 31, 2014 |  |  | 4,267 |  | $ | 6.58 |  |  | 5.7 |  | $ | 10,946 |
Exercisable at December 31, 2014 |  |  | 3,053 |  | $ | 5.83 |  |  | 4.9 |  | $ | 10,014 |
Summary of nonvested RSU activity under the 2014 Plan |
|  | Number of Shares (000's) |  | Weighted Average Grant Date Fair Value |
Nonvested at December 31, 2012 |  |  | — |  | $ | — |
Granted |  |  | 799 |  | $ | 6.21 |
Vested |  |  | (6 | ) | $ | 6.39 |
Canceled/forfeited |  |  | (40 | ) | $ | 6.05 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Nonvested at December 31, 2013 |  |  | 753 |  | $ | 6.22 |
Granted |  |  | 1,650 |  | $ | 6.02 |
Vested |  |  | (868 | ) | $ | 6.09 |
Canceled/forfeited |  |  | (150 | ) | $ | 6.02 |
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Nonvested at December 31, 2014 |  |  | 1,385 |  | $ | 6.09 |
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