Financing (Schedule of Long term Debt) (Details) - USD ($) $ in Thousands	Sep. 29, 2018	Sep. 30, 2017	Jul. 02, 2016
Debt Instrument [Line Items]
Long-term debt, gross	$ 400,706	$ 474,309
Less: Unamortized underwriting discounts, commissions and other expenses	(8,623)	(12,491)
Total long-term debt, less current maturities, net	355,640	418,544
Debt issuance costs	3,705	4,179
Term Loan B Facility [Member]
Debt Instrument [Line Items]
Long-term debt, gross	391,416	455,400
Current maturities	$ (28,600)	(33,600)
Debt instrument, amortization percentage	1.00%
Interest rate, percentage	1.00%
Tangible Equity Units Senior Amortizing Note [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 7,290	16,443
Current maturities	$ (7,290)	(9,152)
Interest rate, percentage	8.75%		8.75%
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capital Lease Obligations	$ 2,000	2,466
Capital lease obligations, current	$ (553)	$ (522)

Debt Instrument, Principal Amount, Amortization Percentage

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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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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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