v3.19.3.a.u2
Derivatives and Hedging - Additional Information (Detail) - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Derivative [Line Items]    
Derivative maximum risk of loss $ 17 $ 17
Forward Foreign Currency Exchange Contracts [Member]    
Derivative [Line Items]    
Notional value 3,400 2,200
Total Return Swaps [Member]    
Derivative [Line Items]    
Notional value $ 644 $ 483