Share-based Compensation Plans and Awards - Fair Value Assumptions Stock Options (Details) (Stock options [Member], USD $)
9 Months Ended
Sep. 30, 2011
Stock options [Member]
 
Weighted-average assumptions used to estimate the fair values of the stock options  
Expected life (in years) 5 years 6 months
Risk-free interest rate 1.97%
Expected volatility 56.00%
Expected dividend yield 0.00%
Weighted-average estimated fair value of options granted during the period (usd per share) $ 16.64