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, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	$ 18	$ (63)	$ 31	$ (135)
Foreign currency exchange derivatives \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	(4)	(9)	(7)	(17)
Foreign currency exchange derivatives \| Net financing charges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	20	(54)	36	(118)
Foreign currency exchange derivatives \| Selling, general and administrative
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in income on derivative	2	0	2	0
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other comprehensive income (loss), cash flow hedge, gain (loss), before reclassification and tax	6	(2)	(12)	(2)
Amount of gain (loss) reclassified from AOCI into income	4	(5)	(3)	(9)
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	2	3	4	(9)
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	4	(6)	1	(2)
Cash Flow Hedging \| Commodity derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Other comprehensive income (loss), cash flow hedge, gain (loss), before reclassification and tax	4	(6)	5	1
Cash Flow Hedging \| Commodity derivatives \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) reclassified from AOCI into income	0	1	(4)	(7)
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	0	1	(21)	6
Net Investment Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains (losses) related to net investment hedges recorded in other comprehensive income	$ 44	$ 30	$ (3)	$ (299)

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, 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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