Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies (Details)

v2.4.0.6
Summary of Significant Accounting Policies (Details) (USD $)
3 Months Ended 9 Months Ended 3 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Jan. 01, 2009
Sep. 30, 2012
United Kingdom
Change in Corporate Income Tax Rate [Member]
Sep. 30, 2011
United Kingdom
Change in Corporate Income Tax Rate [Member]
Jul. 17, 2012
United Kingdom
Change in Corporate Income Tax Rate [Member]
Jul. 19, 2011
United Kingdom
Change in Corporate Income Tax Rate [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]                  
Value assigned to equity interest to the acquired reporting entity         $ 29,100,000,000        
Reduction in Statutory Corporate Income Tax Rate               2.00% 2.00%
Statutory Corporate Income Tax Rate               23.00% 25.00%
Income tax provision (benefit) $ 191,000,000 $ (523,000,000) $ (735,000,000) $ (1,329,000,000)   $ 781,000,000 $ 774,000,000