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Financial Instruments (Schedule Of Derivative Instruments) (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2020 USD ($) lb	Dec. 31, 2019 USD ($)	Sep. 30, 2019 EUR (€)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	$ 0	$ 10
Gain (loss) to other comprehensive income	(35)	1
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	3	(3)
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	7
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of foreign currency hedge positions	2,200
Foreign Exchange Contract [Member] \| Other deductions, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(4)	8
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	0	7
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	27	17
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	1	(2)
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	5	3
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	(80)	$ (26)
All Commodity Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of commodities hedged	$ 81
Copper and Aluminum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Weight in pounds of copper and aluminum commodity hedges \| lb	33
Senior Notes [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt, face amount \| €			€ 1,500