Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Oct. 01, 2019	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Salaries, wages and other benefits	$ 67,766		$ 35,206
Obligation under finance leases	11,362		17,859
Third party commissions	9,270		11,394
Taxes, other than income	5,316		5,215
Insurance liabilities	3,954		4,895
Provisions for litigation	2,580		1,533
Severance payments	970		655
Earn-outs related to acquisitions	295		611
Other	29,109		24,471
Accrued expenses and other liabilities	143,389	$ 115,435	101,839
Accrued Liabilities
Lessee, Lease, Description [Line Items]
Obligation under operating leases	$ 12,767		$ 0

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. 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. 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 the obligations incurred through that date and payable for employees' services provided. 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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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

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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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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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