Financial Instruments - Derivative Instruments Notional Amount Outstanding (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Forward Contracts
Schedule Of Information By Major Category Of Credit Derivatives Contracts [Line Items]
Derivative instruments outstanding	$ 121	$ 221
Currency Swap
Schedule Of Information By Major Category Of Credit Derivatives Contracts [Line Items]
Derivative instruments outstanding	300	300
Commodity Contract
Schedule Of Information By Major Category Of Credit Derivatives Contracts [Line Items]
Derivative instruments outstanding	$ 5	$ 0