Fair Value Measurements - Carrying Value and Estimated Fair Value of Long-term Debt and Finance Leases, Including Current Maturities (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Long-term debt and finance leases, including current maturities, carrying value	$ 400,069	$ 538,274
Long-term debt and finance leases, including current maturities, fair value	$ 376,800	$ 493,600

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-SubTopic 10
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Name:	us-gaap_DebtInstrumentFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant