Share-Based Compensation Arrangement by Share-Based Payment Award, Award Performance Period

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Tax benefit (expense) from stock options exercised.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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

Number of shares authorized for issuance under share-based payment arrangement.

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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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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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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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STOCK-BASED COMPENSATION - Narrative (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance restricted stock units, performance period	3 years
Stock based compensation expenses	$ 25,835	$ 18,704	$ 18,105
Income tax benefit stock based compensation expenses	6,200	3,600	4,100
Unvested stock compensation not recognized	$ 20,800
Unvested stock awards weighted average remaining period of recognition	1 year 8 months 12 days
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of stock options exercised	$ 17,600	3,500	3,000
Tax benefit (expense) from stock options exercised	9,400	(1,900)	700
Employee Stock Option \| Type 1 and Type 3 Modification
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement incremental compensation	1,900
Service Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of vested restricted stock awards/units	2,700	2,600	4,200
Service Based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of vested restricted stock awards/units	$ 9,100	7,300	2,300
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance restricted stock units, performance period	3 years
Performance Shares \| Type 1 and Type 3 Modification
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation by share based payment arrangement incremental compensation	$ 1,400
Selling, General and Administrative Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expenses	$ 25,800	$ 18,700	$ 18,100
2020 Omnibus Incentive Compensation Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum number of shares authorized under share based compensation plan (in shares)	15,852,319
Common stock shares reserved for future issuance (in shares)	2,262,732
Stock based compensation period of expiry of stock options	10 years