Annual report pursuant to Section 13 and 15(d)

Stock Option and Purchase Plans (Details 3)

v2.4.0.6
Stock Option and Purchase Plans (Details 3) (USD $)
In Thousands, except Share data, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Summary of the Company's stock option activity and related information      
Option Outstanding at January 1 1,384,538 1,586,860 1,560,158
Options Granted 108,750 70,782 116,317
Options Exercised (225,558) (273,104) (89,615)
Options Forfeited         
Option Outstanding at December 31 1,267,730 1,384,538 1,586,860
Option Exercisable at December 31 973,716 1,067,287 1,196,049
Weighted Average Exercise Price, Outstanding at January 1 $ 8.05 $ 6.70 $ 5.99
Weighted Average Exercise Price, Options Granted $ 21.69 $ 26.93 $ 14.12
Weighted Average Exercise Price, Options Exercised $ 4.40 $ 5.10 $ 3.94
Weighted Average Exercise Price, Options Forfeited         
Weighted Average Exercise Price, Outstanding at December 31 $ 9.87 $ 8.05 $ 6.70
Weighted Average Exercise Price, Exercisable at December 31 $ 8.06 $ 6.56 $ 5.77
Aggregate Intrinsic Value, Outstanding at January 1 $ 20,532 $ 38,778 $ 16,551
Aggregate Intrinsic Value, Options Granted 129 299 289
Aggregate Intrinsic Value, Options Exercised (4,168) (7,112) (1,135)
Aggregate Intrinsic Value, Options Forfeited         
Aggregate Intrinsic Value, Outstanding at December 31 16,493 31,965 15,706
Aggregate Intrinsic Value, Exercisable at December 31 $ 14,431 $ 26,237 $ 12,953