Stock-Based Compensation (Details Textual) (USD $)
3 Months Ended 6 Months Ended
Jun. 30, 2012
Jun. 30, 2012
Jun. 30, 2011
Stock-Based Compensation (Textual) [Abstract]      
Forfeiture rate increased to reduce stock-based compensation expense $ 724,000,000    
Stock options granted, weighted average exercise price   $ 20.75  
Stock Options [Member]
     
Stock-Based Compensation (Textual) [Abstract]      
Stock based compensation program grant stock based awards     12,120,000
Shares available for future issuance 6,999,215 6,999,215  
Stock-based compensation expense, related to restricted stock awards 295,000,000 737,000,000  
Unrecognized compensation costs, net of forfeitures, related to non-vested stock option awards $ 26,700,000 $ 26,700,000  
Stock options granted   320,000  
Stock options granted, weighted average exercise price   $ 20.75  
Stock options, contractual term   7 years  
Stock options vested   1.1  
Aggregate intrinsic value of stock options outstanding $ 18.39 $ 18.39  
Recognized weighted average period related to non-vested stock option awards   3 years 11 days