Components of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Payables And Accruals [Abstract]
Accrued wages and benefits	$ 37,359	$ 26,747
Accrued insurance	78,993	81,443
Other accrued expenses and other current liabilities	10,934	12,649
Total accrued expenses and other current liabilities	$ 127,286	$ 120,839

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
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant