v2.4.0.8
Derivative and Financial Instruments (Details Textual) (USD $)
In Millions, unless otherwise specified
6 Months Ended
Jun. 30, 2013
Dec. 31, 2012
Jun. 30, 2013
Financial instruments [Member]
Jun. 30, 2013
Trade receivables [Member]
Derivative and Financial Instruments [Abstract]        
Restricted cash   $ 748    
Credit Risk [Abstract]        
Aggregate fair value of all derivative instruments in a liability position 122 130    
Collateral was posted for derivative instruments in a liability position 0 0    
Additional collateral, either in the form of cash or letters of credit $ 122      
Terms of financial instruments and trade receivables [Line items]        
Terms of financial instruments and trade receivables     90 days 30 days