Quarterly report pursuant to Section 13 or 15(d)

Amount and Location in the Income Statement for Derivatives Designed as Cash Flow Hedges (Detail)

v3.8.0.1
Amount and Location in the Income Statement for Derivatives Designed as Cash Flow Hedges (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Derivative Instruments in Cash Flow Hedging Relationships    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion) $ (135) $ (47)
Derivative Instruments in Cash Flow Hedging Relationships | Interest rate contracts    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion) 1 0
Derivative Instruments in Cash Flow Hedging Relationships | Foreign exchange contracts    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion) (136) (47)
Non-derivative Instruments in Net Investment Hedging Relationships    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion) (80) (37)
Non-derivative Instruments in Net Investment Hedging Relationships | Foreign exchange contracts    
Derivative Instruments, Gain (Loss) [Line Items]    
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion) $ (80) $ (37)