Share-based Compensation, Conversion Ratio

No definition available.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

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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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Stock-Based Compensation - Narrative (Details)		12 Months Ended
Stock-Based Compensation - Narrative (Details)	Oct. 31, 2016	Sep. 30, 2023 USD ($) shares	Sep. 30, 2022 USD ($) shares	Sep. 30, 2021 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 34,000,000	$ 29,000,000	$ 36,000,000
Income tax benefit recognized for share-based compensation arrangements		$ 0	$ 0	$ 0
Conversion ratio (in shares)	0.1
Stock options granted (in shares) \| shares		0	0	0
Option exercised in period, intrinsic value		$ 1,000,000	$ 1,000,000	$ 7,000,000
Payments made in conjunction with exercise of SARs		$ 0
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Unrecognized compensation related to unvested share arrangements		$ 22,000,000
Recognition period for unrecognized compensation cost		1 year 10 months 24 days
Granted (in shares) \| shares		678,147
Performance shares (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation related to unvested share arrangements		$ 19,000,000
Recognition period for unrecognized compensation cost		1 year 9 months 18 days
Performance period		3 years
Granted (in shares) \| shares		342,889
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period		10 years
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		2 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Stock appreciation rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares) \| shares		0
Payments made in conjunction with exercise of SARs		$ 1,000,000	$ 2,000,000	$ 2,000,000