Segment Information (Consolidated Earnings by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Interest expense, net	$ (9,957)	$ (7,536)	$ (6,216)	$ (6,387)	$ (6,543)	$ (6,411)	$ (6,316)	$ (6,435)	$ (30,096)	$ (25,705)	$ (24,751)
Consolidated earnings before income taxes	79,027	54,417	48,647	37,487	86,765	68,687	50,236	47,059	219,578	252,747	226,486
Aerospace [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	103,082	82,199	72,969	43,553	85,536	67,173	58,227	46,877	301,803	257,813	232,166
Industrial [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	7,907	10,450	10,237	19,344	23,034	20,870	17,089	17,998	47,938	78,991	82,237
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
Segment earnings (loss)	$ (22,005)	$ (30,696)	$ (28,343)	$ (19,023)	$ (15,262)	$ (12,945)	$ (18,764)	$ (11,381)	$ (100,067)	$ (58,352)	$ (63,166)

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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