Intangible Assets, Net (Schedule of Finite-Lived Intangible Assets by Major Class) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Sep. 30, 2015
Gross Carrying Value	$ 443,147		$ 443,147		$ 445,256
Accumulated Amortization	(238,837)		(238,837)		(220,118)
Net Carrying Amount	204,310		204,310		225,138
Amortization expense	6,887	$ 7,224	20,759	$ 22,026
Process Technology [Member]
Gross Carrying Value	99,469		99,469		99,529
Accumulated Amortization	(57,523)		(57,523)		(52,032)
Net Carrying Amount	41,946		41,946		47,497
Customer Relationships [Member]
Gross Carrying Value	323,131		323,131		323,634
Accumulated Amortization	(162,875)		(162,875)		(149,123)
Net Carrying Amount	160,256		160,256		174,511
Intellectual Property [Member]
Gross Carrying Value	19,314		19,314		19,445
Accumulated Amortization	(17,644)		(17,644)		(16,921)
Net Carrying Amount	1,670		1,670		2,524
Other Intangibles [Member]
Gross Carrying Value	1,233		1,233		2,648
Accumulated Amortization	(795)		(795)		(2,042)
Net Carrying Amount	438		438		606
Aerospace [Member]
Gross Carrying Value	358,830		358,830		360,230
Accumulated Amortization	(171,450)		(171,450)		(154,943)
Net Carrying Amount	187,380		187,380		205,287
Aerospace [Member] | Process Technology [Member]
Gross Carrying Value	76,605		76,605		76,605
Accumulated Amortization	(41,775)		(41,775)		(37,411)
Net Carrying Amount	34,830		34,830		39,194
Aerospace [Member] | Customer Relationships [Member]
Gross Carrying Value	282,225		282,225		282,225
Accumulated Amortization	(129,675)		(129,675)		(116,232)
Net Carrying Amount	152,550		152,550		165,993
Aerospace [Member] | Intellectual Property [Member]
Gross Carrying Value	0		0		0
Accumulated Amortization	0		0		0
Net Carrying Amount	0		0		0
Aerospace [Member] | Other Intangibles [Member]
Gross Carrying Value	0		0		1,400
Accumulated Amortization	0		0		(1,300)
Net Carrying Amount	0		0		100
Industrial [Member]
Gross Carrying Value	84,317		84,317		85,026
Accumulated Amortization	(67,387)		(67,387)		(65,175)
Net Carrying Amount	16,930		16,930		19,851
Industrial [Member] | Process Technology [Member]
Gross Carrying Value	22,864		22,864		22,924
Accumulated Amortization	(15,748)		(15,748)		(14,621)
Net Carrying Amount	7,116		7,116		8,303
Industrial [Member] | Customer Relationships [Member]
Gross Carrying Value	40,906		40,906		41,409
Accumulated Amortization	(33,200)		(33,200)		(32,891)
Net Carrying Amount	7,706		7,706		8,518
Industrial [Member] | Intellectual Property [Member]
Gross Carrying Value	19,314		19,314		19,445
Accumulated Amortization	(17,644)		(17,644)		(16,921)
Net Carrying Amount	1,670		1,670		2,524
Industrial [Member] | Other Intangibles [Member]
Gross Carrying Value	1,233		1,233		1,248
Accumulated Amortization	(795)		(795)		(742)
Net Carrying Amount	$ 438		$ 438		$ 506