Cash Flow Hedge [Abstract]

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- References

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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- Definition

The amount of net gains or losses on foreign currency cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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- Definition

Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993

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-Topic 220
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-Section 45
-Paragraph 10A
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-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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Derivative Instruments and Hedging Activities - Location and Amount of Gains and Losses on Derivative Instruments and Related Hedge Items (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	$ 35	$ (12)	$ 27	$ (6)
Foreign Currency Exchange Derivatives \| Cost of Sales
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	(2)	(3)	(6)	(1)
Foreign Currency Exchange Derivatives \| Net Financing Charges
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	(3)	0	(24)	3
Foreign Currency Exchange Derivatives \| Discontinued Operations
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	28	(4)	54	(1)
Equity swap \| Selling, General And Administrative
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	12	(5)	3	(7)
Net Investment Hedging [Member]
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	50	(100)	84	(136)
Cash Flow Hedging
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	18	(6)	12	3
Amount of Gain (Loss) Reclassified from AOCI into Income	(4)	2	(10)	9
Cash Flow Hedging \| Foreign Currency Exchange Derivatives
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	9	(5)	9	1
Cash Flow Hedging \| Foreign Currency Exchange Derivatives \| Cost of Sales
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Amount of Gain (Loss) Reclassified from AOCI into Income	2	(3)	2	(1)
Cash Flow Hedging \| Foreign Currency Exchange Derivatives \| Discontinued Operations
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Amount of Gain (Loss) Reclassified from AOCI into Income	(1)	1	0	1
Cash Flow Hedging \| Commodity Derivatives
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	9	(1)	3	2
Cash Flow Hedging \| Commodity Derivatives \| Cost of Sales
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Amount of Gain (Loss) Reclassified from AOCI into Income	(1)	1	(3)	3
Cash Flow Hedging \| Commodity Derivatives \| Discontinued Operations
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Amount of Gain (Loss) Reclassified from AOCI into Income	$ (4)	$ 3	$ (9)	$ 6