Stock-Based Compensation Stock Based Compensation (RSU) Details 2 (Details) (USD $)
3 Months Ended
Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]  
RSUs granted 942,856
Restricted Stock Units (RSUs) [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]  
Shares Outstanding, Beginning of Period 574,350
RSUs granted 942,856
RSUs forfeited (4,278)
Shares Outstanding, End of Period 1,512,928
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Weighted Average Exercise Price [Roll Forward]  
Weighted Average Fair Value, Beginning of Period, USD per share $ 64.06
Weighted Average Fair Value, RSUs granted, USD per share $ 97.64
Weighted Average Fair Value, RSUs forfeited, USD per share $ 75.03
Weighted Average Fair Value, End of Period, USD per share $ 84.95