Segment Information (Summary of Consolidated Net Sales and Earnings by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Consolidated net sales	$ 720,220	$ 758,844	$ 1,440,575	$ 1,411,655
Interest expense, net	(8,280)	(11,186)	(16,802)	(22,693)
Consolidated earnings before income taxes	107,199	90,168	168,747	151,683
Aerospace [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	474,236	482,954	948,161	875,841
Industrial [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	245,984	275,890	492,414	535,814
Operating Segments [Member] \| Aerospace [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	474,236	482,954	948,161	875,841
Segment earnings (loss)	117,638	101,722	210,549	174,576
Operating Segments [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	245,984	275,890	492,414	535,814
Segment earnings (loss)	25,972	27,128	54,202	56,297
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	$ (28,131)	$ (27,496)	$ (79,202)	$ (56,497)

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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