Financing (Schedule of Long term Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Sep. 30, 2017	Jul. 02, 2016
Debt Instrument [Line Items]
Total long-term debt	$ 423,929	$ 474,309
Less: Unamortized underwriting discounts, commissions and other expenses	(10,137)	(12,491)
Total long-term debt, less current maturities, net	356,523	418,544
Current portion of unamortized underwriting discounts, commissions and other expenses	4,059	4,179
Term loan B facility
Debt Instrument [Line Items]
Total long-term debt	409,716	455,400
Current maturities	$ (47,252)	$ (33,600)
Principal amount, amortization percentage	1.00%	1.00%
Tangible equity units senior amortizing note
Debt Instrument [Line Items]
Total long-term debt	$ 11,945	$ 16,443
Current maturities	$ (9,474)	(9,152)
Interest rate, percentage	8.75%		8.75%
Capital lease obligations
Debt Instrument [Line Items]
Capital lease obligations	$ 2,268	2,466
Less: Current maturities of capital lease obligations	$ (543)	$ (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 of capital lease obligation due within one year or the normal operating cycle, if longer.

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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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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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