v2.4.0.6
Stockholders Equity - Additional Information (Detail) (USD $)
Share data in Millions, except Per Share data, unless otherwise specified
 12 Months Ended 12 Months Ended 1 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2012
Restricted Stock Units
Dec. 31, 2011
Restricted Stock Units
Jan. 31, 2010
Share Repurchase Program, 2010
Stockholders Equity Note [Line Items]            
Preferred Stock, authorized shares 500 500        
Preferred stock, par value $ 0.01 $ 0.01        
Common shares outstanding plus shares underlying outstanding stock awards, including all stock-based awards outstanding, excluding estimated forfeiture 470 468 465      
Repurchase program authorized by Board of Directors           $ 2,000,000,000
Repurchase program authorized, remaining common stock           763,000,000
Restricted stock unit award service term vesting period (in years), minimum       2 years    
Restricted stock unit award service term vesting period (in years), maximum       5 years    
Net unrecognized compensation cost related to unvested stock-based compensation arrangements 1,300,000,000          
Net unrecognized compensation cost related to unvested stock-based compensation arrangements, weighted average recognition period (in years) 1 year 2 months 12 days          
Restricted stock units that vested, fair value       $ 928,000,000 $ 1,000,000,000  
Matching contributions under 401(k) savings plan, common stock granted 0.1 0.1        
Common stock available for future issuance to employees 149