Accrued Liabilities (Accrued Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Accrued Liabilities [Line Items]
Salaries and other member benefits	$ 88,643	$ 91,285
Warranties	20,130	13,597	$ 15,993	$ 13,741
Interest payable	18,611	9,626
Current portion of acquired performance obligations and unfavorable contracts	1,627	1,627
Accrued retirement benefits	3,571	2,413
Restructuring Reserve, Current	16,522	0
Current portion of deferred income from JV formation (Note 4)	7,087	6,451
Deferred revenues	2,572	4,625
Taxes, other than income	21,128	14,401
Other	13,377	9,704
Accrued liabilities	194,513	155,072
Loss Reserve On Contractual Lease Commitments [Member]
Accrued Liabilities [Line Items]
Restructuring Reserve, Current	$ 1,245	$ 1,343

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of liability, recognized in statement of financial position, for pension, other postretirement and postemployment benefits, classified as current.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Accrued Liabilities [Line Items]

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The current liabilities recognized in the balance sheet that are associated with unfavorable contracts assumed in an acquisition of an entity as well as commitments for the acquired entity to continue to provide services to the seller of the acquired entity, for which the company will be paid by the seller of the acquired entity.

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The carrying amount as of the balance sheet date of deferred income recorded in connection with the formation of a joint venture which is expected to be recognized within one year or the normal operating cycle, if longer. The Company contributed certain contractual rights and intellectual property to a joint venture for which it had no cost basis. The joint venture partner then paid the Company for its ownership interest in the joint venture. The transaction was not the culmination of an earnings event and therefore the consideration received was recorded as deferred income to be recognized/amortized over the estimated remainig lives of the underlying programs assigned to the joint venture.

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