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Financial Instruments (Schedule Of Derivative Instruments) (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2021 USD ($) lb	Mar. 31, 2020 USD ($)	Mar. 31, 2021 USD ($) lb	Mar. 31, 2020 USD ($)	Sep. 30, 2019 EUR (€)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	$ 40	$ 15	$ 40	$ 25
Gain (loss) to other comprehensive income	64	(40)	29	(39)
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	8	(1)	11	(4)
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	13	(23)	26	(16)
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of foreign currency hedge positions	2,100		2,100
Foreign Exchange Contract [Member] \| Other deductions, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	29	13	25	21
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	2	4	2	11
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	0	(66)	27	(49)
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	1	(1)	2	(3)
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	(2)	(8)	3	(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	53	$ 57	(27)	$ 31
All Commodity Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of commodities hedged	$ 111		$ 111
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