Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expenses	$ 5,626	$ 4,928	$ 9,583	$ 8,944
Income tax benefit stock based compensation expenses	1,100	1,100	1,800	1,900
Unvested stock compensation not recognised	35,100		$ 35,100
Unvested stock awards weighted average remaining period of recognition			1 year 10 months 24 days
Selling, General and Administrative Expense [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expenses	$ 5,600	$ 4,900	$ 9,600	$ 8,900
2020 Omnibus Incentive Compensation Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum number of shares authorised under share based compensation plan	15,852,319		15,852,319
Common stock shares reserved for future issuance	2,639,181		2,639,181
Stock based compensation period of expiry of stock options			10 years

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

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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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