Intangible Assets, Net (Schedule of Finite-Lived Intangible Assets by Major Class) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2014
Gross Carrying Value	$ 453,609		$ 453,609		$ 454,187
Accumulated Amortization	(220,992)		(220,992)		(199,415)
Net Carrying Amount	232,617		232,617		254,772
Amortization expense	7,224	$ 8,357	22,026	$ 25,498
Process Technology [Member]
Gross Carrying Value	99,885		99,885		99,683
Accumulated Amortization	(50,401)		(50,401)		(44,860)
Net Carrying Amount	49,484		49,484		54,823
Customer Relationships [Member]
Gross Carrying Value	323,791		323,791		323,931
Accumulated Amortization	(144,192)		(144,192)		(129,313)
Net Carrying Amount	179,599		179,599		194,618
Intellectual Property [Member]
Gross Carrying Value	19,473		19,473		19,954
Accumulated Amortization	(16,616)		(16,616)		(15,938)
Net Carrying Amount	2,857		2,857		4,016
Other Intangibles [Member]
Gross Carrying Value	10,460		10,460		10,619
Accumulated Amortization	(9,783)		(9,783)		(9,304)
Net Carrying Amount	677		677		1,315
Aerospace [Member]
Gross Carrying Value	367,930		367,930		367,930
Accumulated Amortization	(156,434)		(156,434)		(137,465)
Net Carrying Amount	211,496		211,496		230,465
Aerospace [Member] | Process Technology [Member]
Gross Carrying Value	76,605		76,605		76,605
Accumulated Amortization	(35,989)		(35,989)		(31,719)
Net Carrying Amount	40,616		40,616		44,886
Aerospace [Member] | Customer Relationships [Member]
Gross Carrying Value	282,225		282,225		282,225
Accumulated Amortization	(111,495)		(111,495)		(97,281)
Net Carrying Amount	170,730		170,730		184,944
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	9,100		9,100		9,100
Accumulated Amortization	(8,950)		(8,950)		(8,465)
Net Carrying Amount	150		150		635
Energy [Member]
Gross Carrying Value	85,679		85,679		86,257
Accumulated Amortization	(64,558)		(64,558)		(61,950)
Net Carrying Amount	21,121		21,121		24,307
Energy [Member] | Process Technology [Member]
Gross Carrying Value	23,280		23,280		23,078
Accumulated Amortization	(14,412)		(14,412)		(13,141)
Net Carrying Amount	8,868		8,868		9,937
Energy [Member] | Customer Relationships [Member]
Gross Carrying Value	41,566		41,566		41,706
Accumulated Amortization	(32,697)		(32,697)		(32,032)
Net Carrying Amount	8,869		8,869		9,674
Energy [Member] | Intellectual Property [Member]
Gross Carrying Value	19,473		19,473		19,954
Accumulated Amortization	(16,616)		(16,616)		(15,938)
Net Carrying Amount	2,857		2,857		4,016
Energy [Member] | Other Intangibles [Member]
Gross Carrying Value	1,360		1,360		1,519
Accumulated Amortization	(833)		(833)		(839)
Net Carrying Amount	$ 527		$ 527		$ 680