Quarterly report pursuant to Section 13 or 15(d)

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

v2.4.0.6
Stock-Based Awards Stock-Based Awards (Summary of Stock-Based Awards Granted) (Details) (USD $)
3 Months Ended
Mar. 31, 2013
Stock appreciation rights [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Awards Granted 335,999
Weighted Average per Share Fair Value $ 22.62
Restricted stock units [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Awards Granted 158,977
Weighted Average per Share Fair Value $ 59.27
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