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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, 2020 USD ($) lb	Mar. 31, 2019 USD ($)	Mar. 31, 2020 USD ($) lb	Mar. 31, 2019 USD ($)	Sep. 30, 2019 EUR (€)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	$ 15	$ 30	$ 25	$ 40
Gain (loss) to other comprehensive income	(40)	38	(39)	19
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	(23)	10	(16)	3
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(1)	(3)	(4)	(6)
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	13	29	21	40
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	4	5	11	9
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	(66)	23	(49)	12
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	(1)	(1)	(3)	(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	(8)	(1)	(5)	(2)
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	57	6	31	6
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	$ 122		$ 122
Copper and Aluminum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Weight in pounds of copper and aluminum commodity hedges \| lb	50		50
Senior Notes [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt, face amount \| €					€ 1,500