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Share-Based Payments - Stock Incentive Plans (Details) - 2020 Stock Incentive Plan shares in Millions	12 Months Ended
	Sep. 30, 2023 shares
Share-based Payments
Securities available for future issuance (in shares)	10.2
Employee Stock Option
Share-based Payments
Expiration term of unexercised options	7 years

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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