Financing (Schedule of Long term Debt) (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Sep. 28, 2019
Debt Instrument [Line Items]
Long-term debt	$ 522,545
Capital lease obligations		$ 1,436
Total long-term debt		525,131
Less: Unamortized underwriting discounts, commissions and other expenses	(9,729)	(10,313)
Less: Current maturities of tranche B term loan debt	(27,494)
Less: Current maturities of capital lease obligations		(570)
Total long-term debt, less current maturities, net	483,216
Total long-term debt, less current maturities, net		484,648
Current portion of unamortized underwriting discounts, commissions and other expenses	2,106	2,201
Term loan B facility
Debt Instrument [Line Items]
Long-term debt	172,545	173,695
Less: Current maturities of tranche B term loan debt	$ (29,600)	$ (29,600)
Principal amount, amortization percentage	1.00%	1.00%
Unsecured Debt
Debt Instrument [Line Items]
Long-term debt	$ 350,000	$ 350,000
Interest rate, percentage	5.75%

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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