Financial Instruments - Derivative Foreign Currency Contracts at Gross Fair Value and Unrecognized Impacts of Master Netting Arrangements (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Offsetting [Abstract]
Assets, Gross amounts presented in consolidated balance sheets	$ 34	$ 101
Assets, Gross amounts not offset in consolidated balance sheets	33	47
Assets, Net amounts	1	54
Liabilities, Gross amounts presented in Consolidated Balance Sheets	(101)	(49)
Liabilities, Gross amounts not offset in Consolidated Balance Sheets	(33)	(47)
Liabilities, Net Amounts	$ (68)	$ (2)

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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