Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Awards Stock-Based Awards (Summary of Stock-Based Awards Granted) (Details)

v2.4.0.8
Stock-Based Awards Stock-Based Awards (Summary of Stock-Based Awards Granted) (Details) (USD $)
6 Months Ended
Jun. 30, 2013
Stock appreciation rights [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Awards Granted 346,301
Weighted Average per Share Fair Value $ 22.57
Restricted stock units [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Awards Granted 190,424
Weighted Average per Share Fair Value $ 58.52
Employee stock purchase plan options [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Awards Granted 22,232
Weighted Average per Share Fair Value $ 11.32