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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Debt and Financing Arrangements - Additional Information (Detail) € in Millions, $ in Millions	9 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2022 EUR (€)	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Commercial Paper	$ 1,600		$ 0
$2.5 billion facility expiring Dec 2024 [Domain]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,500
$500 million facility expiring Dec 2022 [Domain]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	500
Bank term loan due October 2022
Debt Instrument [Line Items]
Proceeds from Short-term Debt	208	€ 200
Bank term loans due March 2023
Debt Instrument [Line Items]
Proceeds from Short-term Debt	$ 297	€ 285