v2.4.0.8
Shareholders' Equity (Details) (USD $)
In Millions, except Per Share data, unless otherwise specified
0 Months Ended 1 Months Ended 3 Months Ended 6 Months Ended
Jun. 19, 2013
May 31, 2013
item
Mar. 31, 2012
Jun. 30, 2013
subsidiary
Jun. 30, 2013
subsidiary
Jun. 30, 2012
Dec. 31, 2012
May 31, 2011
item
Distribution of qualifying additional paid-in capital                
Proposed U.S. dollar-denominated dividend   $ 816            
Number of quarterly installments (in installments)   4           4
Cash distribution approved in the form of additional paid-in capital (in dollars per share)   $ 2.24           $ 3.16
Amount of installment (in dollars per share)   $ 0.56           $ 0.79
Installment of dividend paid 204   278 204 204 278    
Unpaid distribution payable       $ 612 $ 612      
Shares held by subsidiary                
Number of subsidiaries to whom shares were issued       1 1      
Number of shares held by subsidiary       10.6 10.6   11.5