| Stock option activity |
The following summarizes the activity under the Company’s stock option plans in the nine months ended September 30, 2016: | | | | | | | | | | | | | Number of Options (#) | | Weighted Average Exercise Price ($) | | Aggregate Intrinsic Value ($) | | | | | | (In thousands) | Balance, December 31, 2015 | 2,999,199 |
| | $ | 31.37 |
| | | Granted | 967,918 |
| | $ | 31.32 |
| | | Exercised(1) | (226,296 | ) | | $ | 19.54 |
| | $ | 4,440 |
| Canceled | (198,885 | ) | | $ | 32.60 |
| | | Balance, September 30, 2016 | 3,541,936 |
| | $ | 32.05 |
| | $ | 32,243 |
| Vested, September 30, 2016(2) | 1,347,219 |
| | $ | 31.63 |
| | $ | 12,837 |
| Vested and expected to vest, September 30, 2016(2)(3) | 3,230,071 |
| |
| | $ | 29,427 |
|
| | (1) | The aggregate intrinsic value was calculated based on the positive difference between the pre-tax fair value of the Company’s common stock as of the date of exercise and the exercise price of the underlying options. |
| | (2) | The aggregate intrinsic value was calculated based on the positive pre-tax difference between the closing price of the Company’s common stock as of September 30, 2016, and the exercise price of the underlying options. |
| | (3) | Represents the number of vested options as of September 30, 2016, plus the number of unvested options expected to vest as of September 30, 2016, based on the unvested options outstanding at September 30, 2016, adjusted for the estimated forfeiture. |
|
| Summary of restricted stock units |
The following table summarizes the status of the Company’s restricted stock units in the nine months ended September 30, 2016: | | | | | | | | | Number of Shares (#) | | Weighted Average Grant Date Fair Value ($) | Balance, December 31, 2015 | 811,965 |
| | $ | 32.30 |
| Granted | 581,777 |
| | 29.69 |
| Vested | (309,024 | ) | | 30.73 |
| Forfeited | (112,904 | ) | | 33.23 |
| Balance, September 30, 2016 | 971,814 |
| | $ | 31.14 |
|
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