Schedule Of Effect Of Derivatives Recognized (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Cost-method Investments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$ 15	$ 15	$ 18
Derivatives not designated as hedging instruments		58	79	$ 46
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	13	13	13
Interest Expense [Member]
Schedule of Cost-method Investments [Line Items]
Derivatives not designated as hedging instruments		68	32	10
Operating Expense [Member]
Schedule of Cost-method Investments [Line Items]
Derivatives not designated as hedging instruments		26		2
Derivative Instruments Gain Loss Recognized In Operations			16
Designated as Hedging Instrument \| Interest Rate Swap [Member]
Schedule of Cost-method Investments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	7	7	1
Interest rate swaps		4	(1)	(2)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	4	4	5
Designated as Hedging Instrument \| Foreign Exchange Forward [Member]
Schedule of Cost-method Investments [Line Items]
Interest rate swaps	83	14	34	46
Not Designated as Hedging Instrument \| Foreign Exchange Forward [Member]
Schedule of Cost-method Investments [Line Items]
Derivatives not designated as hedging instruments		42	48	8
Not Designated as Hedging Instrument \| Currency Swap [Member]
Schedule of Cost-method Investments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	7	7	16
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	2	2	2
Not Designated as Hedging Instrument \| Interest Rate Contract
Schedule of Cost-method Investments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	1	1	1
Derivatives not designated as hedging instruments		(2)	(2)	(3)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	7	7	5
Not Designated as Hedging Instrument \| Commodity Contract
Schedule of Cost-method Investments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	0	0
Derivatives not designated as hedging instruments		0	0	$ (3)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ 0	$ 0	$ 1

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313

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Fair value, after offset of derivative asset, of financial liability or 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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-Publisher FASB
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