Financial Instruments (Fair Values Of Derivatives Instruments) (Detail) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Fair Value, Asset Derivatives	$ 4	$ 5
Fair Value, Liability Derivatives	71	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	62	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	4	5
Fair Value, Liability Derivatives	5	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	1	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	$ 3	$ 0