Financial Instruments (Fair Values Of Derivatives Instruments) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Fair Value, Asset Derivatives	$ 22	$ 5
Fair Value, Liability Derivatives	92	38
Designated As Hedging Instruments [Member] | Interest Rate Swaps [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Fair Value, Asset Derivatives	0	0
Fair Value, Liability Derivatives	51	27
Not Designated As Hedging Instruments [Member] | Foreign Exchange Contract [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Fair Value, Asset Derivatives	22	5
Fair Value, Liability Derivatives	31	10
Not Designated As Hedging Instruments [Member] | Interest Rate Contracts [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Fair Value, Asset Derivatives	0	0
Fair Value, Liability Derivatives	3	1
Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Fair Value, Asset Derivatives	0	0
Fair Value, Liability Derivatives	$ 7	$ 0