Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expenses	$ 4,928	$ 7,156	$ 8,944	$ 10,136
Income tax benefit stock based compensation expenses	1,100	300	1,900	800
Unvested stock compensation not recognised	35,600		$ 35,600
Unvested stock awards weighted average remaining period of recognition			2 years 3 months 18 days
Selling, General and Administrative Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expenses	$ 4,900	$ 7,200	$ 8,900	$ 10,100
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	3,849,011		3,849,011
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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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 option under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award 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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