Revenue Recognition - Summary of Changes in Allowance for Credit Losses (Detail) $ in Thousands	12 Months Ended
Sep. 30, 2025 USD ($)
Revenue from Contract with Customer [Abstract]
Balance as of September 30, 2024	$ 6,434
Current period provision	6,879
Write-offs, net and other	(6,117)
Balance as of September 30, 2025	$ 7,196

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
-Topic 326
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Reference 2: 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