Segment Information (Consolidated Net Sales and Earnings by Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Net sales	$ 565,447	$ 524,284	$ 482,467	$ 429,042	$ 558,365	$ 483,759	$ 485,513	$ 408,339	$ 2,001,240	$ 1,935,976	$ 1,865,627
Segment earnings (loss)									293,478	265,062	256,633
Interest expense, net	(4,503)	(5,899)	(6,128)	(6,003)	(6,439)	(6,655)	(6,948)	(6,388)	(22,533)	(26,430)	(25,461)
Consolidated earnings before income taxes	75,076	62,468	56,756	32,944	75,201	35,497	50,336	38,537	227,244	199,571	197,807
Total of Reporting Segments [Member]
Net sales	565,447	524,284	482,467	429,042	558,365	483,759	485,513	408,339
Segment earnings (loss)	92,121	79,560	72,177	49,620	92,749	51,379	65,458	55,476
Aerospace [Member]
Net sales	318,209	274,923	261,021	229,872	307,377	272,218	270,493	211,389	1,084,025	1,061,477	896,083
Segment earnings (loss)	57,005	39,357	40,289	22,549	54,382	38,949	41,223	31,568	159,200	166,122	130,192
Energy [Member]
Net sales	247,238	249,361	221,446	199,170	250,988	211,541	215,020	196,950	917,215	874,499	969,544
Segment earnings (loss)	35,116	40,203	31,888	27,071	38,367	12,430	24,235	23,908	134,278	98,940	126,441
Unallocated Corporate [Member]
Segment earnings (loss)	$ (12,542)	$ (11,193)	$ (9,293)	$ (10,673)	$ (11,109)	$ (9,227)	$ (8,174)	$ (10,551)	$ (43,701)	$ (39,061)	$ (33,365)