Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Debt (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended
Debt (Narrative) (Details) - USD ($)	Oct. 31, 2023	Mar. 31, 2024	Feb. 29, 2024	Dec. 31, 2023	Nov. 30, 2023	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Commercial paper outstanding		$ 50,000,000		$ 0
Debt, weighted average interest rate							5.19%
Other Debt Facilities
Debt Instrument [Line Items]
Revolving credit facility, amount outstanding		0		0
Other credit and overdraft facilities		114,000,000		113,000,000
Letters of credit		$ 128,000,000		139,000,000
3.875% Senior Debt Obligations October 2024
Debt Instrument [Line Items]
Interest rate		3.875%
Senior notes – 5.150% due 2034
Debt Instrument [Line Items]
Interest rate		5.15%	5.15%
Senior notes – 5.450% due 2054
Debt Instrument [Line Items]
Interest rate		5.45%	5.45%
4.05% Senior Debt Obligations October 2023
Debt Instrument [Line Items]
Interest rate	4.05%
Senior notes – 5.400% due 2033
Debt Instrument [Line Items]
Interest rate		5.40%				5.40%
5.700% Senior Debt Obligations Due 2053
Debt Instrument [Line Items]
Interest rate						5.70%
Senior notes – 5.450% due 2053
Debt Instrument [Line Items]
Interest rate		5.45%					5.45%
Commercial paper
Debt Instrument [Line Items]
Short-term debt	$ 2,800,000,000				$ 3,500,000,000			$ 2,000,000,000
Effective interest rate (percent)		5.45%
Revolving credit facility
Debt Instrument [Line Items]
Debt instrument, term	5 years
Revolving credit facility, borrowing capacity	$ 3,500,000,000
Revolving credit facility \| New Facility
Debt Instrument [Line Items]
Revolving credit facility, borrowing capacity						$ 2,800,000,000
Revolving credit facility, amount outstanding		$ 0		$ 0
Revolving credit facility \| Uncommitted Credit Facility
Debt Instrument [Line Items]
Debt instrument, term	1 year
Revolving credit facility, amount outstanding							$ 250,000,000
Senior Notes \| 3.875% Senior Debt Obligations October 2024
Debt Instrument [Line Items]
Repayments of debt		$ 1,000,000,000
Senior Notes \| Senior notes – 5.150% due 2034
Debt Instrument [Line Items]
Debt instrument face amount			$ 500,000,000
Senior Notes \| Senior notes – 5.450% due 2054
Debt Instrument [Line Items]
Debt instrument face amount			$ 500,000,000
Senior Notes \| 4.05% Senior Debt Obligations October 2023
Debt Instrument [Line Items]
Repayments of debt	$ 250,000,000
Senior Notes \| Senior notes – 5.400% due 2033
Debt Instrument [Line Items]
Debt instrument face amount						600,000,000
Senior Notes \| 5.700% Senior Debt Obligations Due 2053
Debt Instrument [Line Items]
Debt instrument face amount						$ 1,000,000,000
Senior Notes \| Senior notes – 5.450% due 2053
Debt Instrument [Line Items]
Debt instrument face amount							$ 600,000,000