Accrued Liabilities (Changes in Restructuring Reserve Activity) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges, beginning of period	$ 16,522
Charges (gains)		17,013
Cash receipts (payments)	(12,445)	(491)
Non-cash adjustments	(3,570)
Restructuring charges, end of period	507	16,522
Duarte Plant Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges, beginning of period	12,504
Charges (gains)		12,504
Cash receipts (payments)	(8,685)
Non-cash adjustments	(3,379)
Restructuring charges, end of period	440	12,504
Industrial Turbomachinery Business Realignment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges, beginning of period	4,018
Charges (gains)		4,509
Cash receipts (payments)	(3,760)	(491)
Non-cash adjustments	(191)
Restructuring charges, end of period	$ 67	4,018
Duarte Plant Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Charges (gains)		$ 17,013

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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