Segment Information (Summary of Consolidated Net Sales and Earnings by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Net sales	$ 652,811	$ 470,148
Interest expense, net	(11,507)	(8,509)
Consolidated earnings before income taxes	61,515	37,487
Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	392,887
Industrial [Member]
Segment Reporting Information [Line Items]
Net sales	259,924
Operating Segments [Member] \| Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	392,887	305,905
Segment earnings (loss)	72,854	45,241
Operating Segments [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Net sales	259,924	164,243
Segment earnings (loss)	29,169	19,781
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	$ (29,001)	$ (19,026)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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