Balance Sheet Details (Schedule Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 523,727	$ 348,239
Other		(9)
Adjustment to goodwill	(6,116)
Goodwill, Ending Balance	556,957	523,727
Line Rate Systems [Member]
Goodwill [Roll Forward]
Acquisition		99,560
Versafe [Member]
Goodwill [Roll Forward]
Acquisition		75,937
Defense.net [Member]
Goodwill [Roll Forward]
Acquisition	$ 39,346

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

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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 other (increase) decrease of an asset representing the 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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Amount of (increase) decrease to an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from the subsequent recognition of deferred tax assets.

+ References

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