Financing (Schedule of Long term Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017	Jul. 02, 2016
Debt Instrument [Line Items]
Total long-term debt	$ 404,409	$ 474,309
Less: Unamortized underwriting discounts, commissions and other expenses	(9,190)	(12,491)
Total long-term debt, less current maturities, net	342,419	418,544
Current portion of unamortized underwriting discounts, commissions and other expenses	3,887	4,179
Term loan B facility
Debt Instrument [Line Items]
Total long-term debt	392,566	455,400
Current maturities	$ (42,600)	$ (33,600)
Principal amount, amortization percentage	1.00%	1.00%
Tangible equity units senior amortizing note
Debt Instrument [Line Items]
Total long-term debt	$ 9,638	$ 16,443
Current maturities	$ (9,638)	(9,152)
Interest rate, percentage	8.75%		8.75%
Capital lease obligations
Debt Instrument [Line Items]
Capital lease obligations	$ 2,205	2,466
Less: Current maturities of capital lease obligations	$ (562)	$ (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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