Detail of Certain Balance Sheet Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Detail of Certain Balance Sheet Accounts [Abstract]
Accounts Receivable, Allowance for Credit Loss, Beginning	$ 2,387
Accounts Receivable, Allowance for Credit Loss, Ending	5,361	$ 2,387
Accounts payable, trade	184,963	136,967
Accrued compensation and benefits	75,190	61,109
Accrued insurance liabilities	7,693	5,787
Current operating lease liabilities	17,319	13,973
Other accrued expenses	31,785	31,278
Accounts payable and accrued expenses	316,950	249,114
Executive Savings Plan assets	706	937
Securities and equity investments	2,447	10
Finance Lease, Right-of-Use Asset, after Accumulated Amortization	10,246	3,927
Other	1,746	2,175
Other non-current assets	$ 15,145	$ 7,049

Detail of Certain Balance Sheet Accounts [Abstract]

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Carrying value as of the balance sheet date of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable to insurance entities to mitigate potential loss from various risks or to satisfy a promise to provide certain coverage's to employees.

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Carrying value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided.

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Amount of allowance for credit loss on accounts receivable.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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