Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation (Details)

v2.4.0.6
Stock Based Compensation (Details) (USD $)
In Millions, except Share data, unless otherwise specified
 1 Months Ended 3 Months Ended
Mar. 05, 2013
Mar. 31, 2013
Dec. 31, 2012
Stock option activity      
Number of Shares Underlying Options, Outstanding at beginning of period   4,065,000  
Number of Shares Underlying Options, Granted 1,116,400 1,116,000  
Number of Shares Underlying Options, Exercised   (32,000)  
Number of Shares Underlying Options, Outstanding at end of period   5,149,000 4,065,000
Number of Shares Underlying Options, Vested - end of period   4,266,000  
Number of Shares Underlying Options, Vested and expected to vest - end of period   4,967,000  
Weighted Average Exercise Price Per Share, Outstanding at beginning of period   $ 6.12  
Weighted Average Exercise Price Per Share, Granted   $ 7.75  
Weighted Average Exercise Price Per Share, Exercised   $ 4.24  
Weighted Average Exercise Price Per Share, Forfeited   $ 0.00  
Weighted Average Exercise Price Per Share, Outstanding at end of period   $ 6.48 $ 6.12
Weighted Average Exercise Price Per Share, Vested - end of period   $ 6.15  
Weighted Average Exercise Price Per Share, Vested and expected to vest - end of period   $ 6.48  
Weighted Average Remaining Contractual Term, Outstanding at beginning of period   2 years 11 months 19 days 2 years 7 months 24 days
Weighted Average Remaining Contractual Term, Granted   4 years 11 months 5 days  
Weighted Average Remaining Contractual Term, Exercised   6 months 11 days  
Weighted Average Remaining Contractual Term, Outstanding at end of period   2 years 11 months 19 days 2 years 7 months 24 days
Weighted Average Remaining Contractual Term, Vested at end of period   2 years 7 months 17 days  
Weighted Average Remaining Contractual Term, Vested and expected to vest - end of period   2 years 11 months 19 days  
Aggregate Intrinsic Value, Outstanding at end of period   $ 10.24  
Aggregate Intrinsic Value, Vested - end of period   9.86  
Aggregate Intrinsic Value, Vested and expected to vest - end of the period   $ 10.16