Segment Information (Summary of Consolidated Net Sales and Earnings by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Consolidated net sales	$ 720,355	$ 652,811
Interest expense, net	(8,522)	(11,507)
Consolidated earnings before income taxes	61,548	61,515
Aerospace [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	473,925	392,887
Industrial [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	246,430	259,924
Operating Segments [Member] \| Aerospace [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	473,925	392,887
Segment earnings (loss)	92,911	72,854
Operating Segments [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	246,430	259,924
Segment earnings (loss)	28,230	29,169
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	$ (51,071)	$ (29,001)

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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