Goodwill and Other Identifiable Intangible Assets, Net (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 76,599	$ 80,413
Accumulated amortization	(71,251)	(73,628)
Net	5,348us-gaap_FiniteLivedIntangibleAssetsNet	6,785us-gaap_FiniteLivedIntangibleAssetsNet
Purchased and Core Technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	45,298	45,952
Accumulated amortization	(44,949)	(45,162)
Net	349	790
License Agreements
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	0	2,440
Accumulated amortization	0	(2,440)
Net	0	0
Patents and Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	11,830	11,667
Accumulated amortization	(10,302)	(9,799)
Net	1,528	1,868
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	18,371	18,894
Accumulated amortization	(15,468)	(15,445)
Net	2,903	3,449
Non-compete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,100	1,100
Accumulated amortization	(532)	(422)
Net	568	678
Order Backlog
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	0	360
Accumulated amortization	0	(360)
Net	$ 0	$ 0

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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=26713463&loc=d3e16323-109275

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