Goodwill and other Identifiable Intangible Assets Goodwill (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Goodwill [Roll Forward]
Beginning balance	$ 86,209	$ 86,012
Acquisition of Etherios, Inc.	17,282	0
Foreign currency translation adjustment	78	197
Ending balance	$ 103,569	$ 86,209

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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