Schedule Of Effect Of Derivatives Recognized (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$ 3	$ 5
Derivatives not designated as hedging instruments	109	11	$ (48)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	80	38
Interest Expense [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivatives not designated as hedging instruments	3	(11)	19
Operating Expense [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivatives not designated as hedging instruments	2	(4)	(12)
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	0	0
Interest rate swaps	(31)	(23)	(4)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	69	27
Designated as Hedging Instrument \| Foreign Exchange Forward [Member]
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Interest rate swaps	(67)	17	24
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	5	7	(31)
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	3	5
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	11	10
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	0	1	3
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	1
Not Designated as Hedging Instrument \| Commodity Contract
Schedule of Cost-method Investments [Line Items] (Deprecated 2018-01-31)
Derivatives not designated as hedging instruments	$ 6	$ (3)	$ 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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