v2.4.0.6
Capital Stock (Details 2) (USD $)
 1 Months Ended 1 Months Ended 1 Months Ended
Feb. 28, 2011
Dec. 31, 2011
Jul. 01, 2011
Dec. 31, 2010
Jul. 31, 2011
NHP
Dec. 31, 2011
NHP
Jul. 01, 2011
NHP
Nov. 30, 2011
ASLG
May 31, 2011
ASLG
May 12, 2011
ASLG
Business acquisition                    
Number of shares reserved for issuance in connection with equity awards and other convertible or exchangeable securities           2,253,366 2,253,366      
Common stock share value issued related to acquisition             $ 5,400,000,000     $ 1,380,000,000
Closing price of Common stock             $ 53.74     $ 55.33
Number of common stock issued related to acquisition         99,849,106       24,958,543  
Number of shares reduced for working capital adjustment with purchase agreement               83,441    
Number of shares of common stock issued and sold in an underwritten public offering 5,563,000                  
Aggregate proceeds from the sale of common stock in an underwritten public offering pursuant $ 300,000,000                  
Capital stock authorized (in shares)   610,000,000 610,000,000              
Common stock, shares authorized   600,000,000 600,000,000 300,000,000            
Common stock, par value (in dollars per share)   $ 0.25 $ 0.25 $ 0.25            
Preferred stock, shares authorized   10,000,000 10,000,000 10,000,000            
Preferred stock, par value (in dollars per share)   $ 1.00 $ 1.00 $ 1.00