Segment Information (Summary of Consolidated Net Sales and Earnings by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Consolidated net sales	$ 752,005	$ 588,117	$ 2,163,660	$ 1,606,514
Interest expense, net	(10,450)	(9,714)	(33,143)	(26,575)
Consolidated earnings before income taxes	92,314	54,417	243,997	140,551
Aerospace [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	498,775		1,374,616
Industrial [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	253,230		789,044
Operating Segments [Member] \| Aerospace [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	498,775	404,612	1,374,616	1,096,860
Segment earnings (loss)	103,238	83,887	277,814	203,784
Operating Segments [Member] \| Industrial [Member]
Segment Reporting Information [Line Items]
Consolidated net sales	253,230	183,505	789,044	509,654
Segment earnings (loss)	26,240	10,943	82,537	41,411
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	$ (26,714)	$ (30,699)	$ (83,211)	$ (78,069)

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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