Revenue Recognition - Summary of Changes in Allowance for Credit Losses (Detail) $ in Thousands	6 Months Ended
Mar. 31, 2024 USD ($)
Revenue from Contract with Customer [Abstract]
Balance at September 30, 2023	$ 8,375
Current period provision	3,672
Write-offs, net and other	(3,151)
Balance as of March 31, 2024	$ 8,896

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant