Derivative Instruments and Hedging Activities - Location and Amount of Gains and Losses on Derivative Instruments and Related Hedge Items (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	$ (63)	$ (19)	$ (135)	$ 75
Foreign currency exchange derivatives \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	(9)	1	(17)	8
Foreign currency exchange derivatives \| Net financing charges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	(54)	(16)	(118)	72
Equity swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	0	(4)	0	(5)
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other comprehensive income (loss), cash flow hedge, gain (loss), before reclassification and tax	(2)	(21)	(2)	6
Amount of gain (loss) reclassified from AOCI into income	(5)	9	(9)	14
Cash Flow Hedging \| Foreign currency exchange derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other comprehensive income (loss), cash flow hedge, gain (loss), before reclassification and tax	3	3	(9)	26
Cash Flow Hedging \| Foreign currency exchange derivatives \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) reclassified from AOCI into income	(6)	14	(2)	25
Cash Flow Hedging \| Commodity derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other comprehensive income (loss), cash flow hedge, gain (loss), before reclassification and tax	(6)	(24)	1	(20)
Cash Flow Hedging \| Commodity derivatives \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) reclassified from AOCI into income	1	(4)	(7)	(9)
Cash Flow Hedging \| Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Other comprehensive income (loss), cash flow hedge, gain (loss), before reclassification and tax	1	0	6	0
Cash Flow Hedging \| Interest rate swaps \| Net financing charges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) reclassified from AOCI into income	$ 0	$ (1)	$ 0	$ (2)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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