Accrued Liabilities (Loss Reserve Activity) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2015	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Charges (gains)			$ 17,013
Loss reserve, noncurrent portion			2,686	$ 3,927
Loss Reserve On Contractual Lease Commitments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges, beginning of period		$ 2,464	5,270	9,242	$ 2,464
Charges (gains)		$ 8,165	0	0	8,165
Payments, net of sublease income			(1,339)	(1,650)	(1,387)
Non-cash adjustments	$ 2,322		0	(2,322)	0
Restructuring charges, end of period			3,931	$ 5,270	$ 9,242
Loss reserve, noncurrent portion			$ 2,686

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next 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, and 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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