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Financial Instruments (Schedule Of Derivative Instruments) (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020 USD ($) lb	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) lb	Jun. 30, 2019 USD ($)	Sep. 30, 2019 EUR (€)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	$ (35)	$ 5	$ (10)	$ 45
Gain (loss) to other comprehensive income	(28)	(2)	(67)	17
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(4)	(2)	(8)	(8)
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	17	(8)	1	(5)
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of foreign currency hedge positions	2,200		2,200
Foreign Exchange Contract [Member] \| Other deductions, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(26)	3	(5)	43
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(3)	6	8	15
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	21	3	(28)	15
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(2)	(2)	(5)	(5)
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	6	(3)	1	(5)
Foreign Exchange Contract [Member] \| Net Investment Hedging [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	(72)	6	(41)	12
Foreign Exchange Contract [Member] \| Net Investment Hedging [Member] \| Other deductions, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income
All Commodity Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of commodities hedged	$ 96		$ 96
Copper and Aluminum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Weight in pounds of copper and aluminum commodity hedges \| lb	39		39
Senior Notes [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt, face amount \| €					€ 1,500