Intangible Assets, Net (Schedule of Finite-Lived Intangible Assets by Major Class) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Gross Carrying Value	$ 443,445	$ 445,256
Accumulated Amortization	(245,795)	(220,118)
Net Carrying Amount	197,650	225,138
Amortization expense	27,486	29,241	$ 33,580
Process Technology [Member]
Gross Carrying Value	99,570	99,529
Accumulated Amortization	(59,429)	(52,032)
Net Carrying Amount	40,141	47,497
Customer Relationships [Member]
Gross Carrying Value	323,194	323,634
Accumulated Amortization	(167,667)	(149,123)
Net Carrying Amount	155,527	174,511
Intellectual Property [Member]
Gross Carrying Value	19,435	19,445
Accumulated Amortization	(17,876)	(16,921)
Net Carrying Amount	1,559	2,524
Other Intangibles [Member]
Gross Carrying Value	1,246	2,648
Accumulated Amortization	(823)	(2,042)
Net Carrying Amount	423	606
Aerospace [Member]
Gross Carrying Value	358,830	360,230
Accumulated Amortization	(177,387)	(154,943)
Net Carrying Amount	181,443	205,287
Aerospace [Member] \| Process Technology [Member]
Gross Carrying Value	76,605	76,605
Accumulated Amortization	(43,229)	(37,411)
Net Carrying Amount	33,376	39,194
Aerospace [Member] \| Customer Relationships [Member]
Gross Carrying Value	282,225	282,225
Accumulated Amortization	(134,158)	(116,232)
Net Carrying Amount	148,067	165,993
Aerospace [Member] \| Intellectual Property [Member]
Gross Carrying Value	0	0
Accumulated Amortization	0	0
Net Carrying Amount	0	0
Aerospace [Member] \| Other Intangibles [Member]
Gross Carrying Value	0	1,400
Accumulated Amortization	0	(1,300)
Net Carrying Amount	0	100
Industrial [Member]
Gross Carrying Value	84,615	85,026
Accumulated Amortization	(68,408)	(65,175)
Net Carrying Amount	16,207	19,851
Industrial [Member] \| Process Technology [Member]
Gross Carrying Value	22,965	22,924
Accumulated Amortization	(16,200)	(14,621)
Net Carrying Amount	6,765	8,303
Industrial [Member] \| Customer Relationships [Member]
Gross Carrying Value	40,969	41,409
Accumulated Amortization	(33,509)	(32,891)
Net Carrying Amount	7,460	8,518
Industrial [Member] \| Intellectual Property [Member]
Gross Carrying Value	19,435	19,445
Accumulated Amortization	(17,876)	(16,921)
Net Carrying Amount	1,559	2,524
Industrial [Member] \| Other Intangibles [Member]
Gross Carrying Value	1,246	1,248
Accumulated Amortization	(823)	(742)
Net Carrying Amount	$ 423	$ 506

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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