Schedule Of Effect Of Derivatives Recognized (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$ 17	$ 11
Derivatives not designated as hedging instruments	(48)	91	$ (58)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	22	8
Interest Expense [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivatives not designated as hedging instruments	19	(23)	68
Operating Expense [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivatives not designated as hedging instruments	12	(19)	(26)
Designated as Hedging Instrument \| Interest Rate Swap [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	12	8
Interest rate swaps	(4)	3	4
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	8	0
Designated as Hedging Instrument \| Foreign Exchange Forward [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Interest rate swaps	24	(50)	14
Not Designated as Hedging Instrument \| Foreign Exchange Forward [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivatives not designated as hedging instruments	(31)	42	(42)
Not Designated as Hedging Instrument \| Currency Swap [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	5	3
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	11	7
Not Designated as Hedging Instrument \| Interest Rate Contract
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	0
Derivatives not designated as hedging instruments	3	1	2
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	2	1
Not Designated as Hedging Instrument \| Commodity Contract
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	0
Derivatives not designated as hedging instruments	0	1	$ 0
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ 1	$ 0

Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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