Components of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Payables And Accruals [Abstract]
Accrued wages and benefits	$ 29,467	$ 37,359
Self-insurance liabilities	80,572	78,993
Other accrued expenses and other current liabilities	11,182	10,934
Total accrued expenses and other current liabilities	$ 121,221	$ 127,286

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant