Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 26, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Deferred financing costs	$ (5,350)	$ (6,569)
Other	0	525
Total debt	846,145	845,317
Less: Current portion	0	0
Long-term debt	846,145	845,317
Secured Debt \| First Lien Term Loan Facility due December 22, 2023
Debt Instrument [Line Items]
First Lien Term Loan Facility due December 22, 2023	$ 851,495	$ 851,361

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt classified as other.

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