|
Stock-Based Compensation (Details 1) (USD $)
In Thousands, except Share data, unless otherwise specified
|
12 Months Ended |
|
Dec. 31, 2012
|
| Summary of stock option activity |
|
| Number of Shares Outstanding at December 31, 2011 |
2,182,940 |
| Number of Shares Granted |
193,500 |
| Number of Shares Cancelled/forfeited |
|
| Number of Shares Exercised |
(428,181) |
| Number of Shares Outstanding at December 31, 2012 |
1,948,259 |
| Number of Shares Exercisable at December 31, 2012 |
1,538,431 |
| Weighted Average Exercise Price, Outstanding at December 31, 2011 |
$ 13.00 |
| Weighted Average Exercise Price, Granted |
$ 22.17 |
| Weighted Average Exercise Price, Cancelled/forfeited |
|
| Weighted Average Exercise Price, Exercised |
$ 6.33 |
| Weighted Average Exercise Price, Outstanding at December 31, 2012 |
$ 15.38 |
| Weighted Average Exercise Price, Exercisable at December 31, 2012 |
$ 13.60 |
| Aggregate Intrinsic Value, Outstanding at December 31, 2012 |
$ 29,700 |
| Aggregate Intrinsic Value, Exercisable at December 31, 2012 |
$ 26,178 |
|
Minimum [Member]
|
|
| Summary of stock option activity |
|
| Option Price Per Share, Outstanding at December 31, 2011 |
$ 0.51 |
| Option Price Per Share, Cancelled/forfeited |
|
| Option Price Per Share, Exercised |
$ 0.51 |
| Option Price Per Share, Outstanding at December 31, 2012 |
$ 2.89 |
| Option Price Per Share, Exercisable at December 31, 2012 |
$ 2.89 |
|
Maximum [Member]
|
|
| Summary of stock option activity |
|
| Option Price Per Share, Outstanding at December 31, 2011 |
$ 24.65 |
| Option Price Per Share, Granted |
$ 22.17 |
| Option Price Per Share, Cancelled/forfeited |
|
| Option Price Per Share, Exercised |
$ 20.09 |
| Option Price Per Share, Outstanding at December 31, 2012 |
$ 24.65 |
| Option Price Per Share, Exercisable at December 31, 2012 |
$ 24.65 |