Intangible Assets (Schedule of Intangible Assets Subject to Amortization) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Sep. 30, 2014
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 12,885	$ 12,885
Accumulated Amortization	(11,278)	(10,981)
Net Carrying Value	1,607us-gaap_FiniteLivedIntangibleAssetsNet	1,904us-gaap_FiniteLivedIntangibleAssetsNet
Purchased Technology
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	11,749	11,749
Accumulated Amortization	(10,165)	(9,918)
Net Carrying Value	1,584	1,831
Trade Name
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	1,136	1,136
Accumulated Amortization	(1,113)	(1,063)
Net Carrying Value	$ 23	$ 73

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

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

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