v2.4.0.6
Amount and Location in the Income Statement for Derivatives Designed as Cash Flow Hedges (Detail) (Cash Flow Hedging, USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) $ (42) $ (11)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) (98) 51
Interest rate contracts | Interest Expense
   
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) (6) 7
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) (19) (18)
Foreign exchange contracts | Interest Expense
   
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) (85) (48)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) 13 (27)
Foreign exchange contracts | Other Operating Expense
   
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) 5  
Foreign exchange contracts | Revenue
   
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) 35 30
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) (101) 96
Commodity Contract | Fuel Expense
   
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion) 9  
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) $ 9