Accrued Expenses and Other Current Liabilities (Schedule of Restructuring and Related Costs) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015	Sep. 30, 2014
Restructuring Reserve [Roll Forward]
Balance as of September 30, 2014	$ 1,317us-gaap_RestructuringReserve
Expense - charged to accrual	1,824us-gaap_RestructuringCharges
Payments and accrual adjustments	(740)
Balance as of March 31, 2015	2,401us-gaap_RestructuringReserve
Current portion	2,309us-gaap_RestructuringReserveCurrent	1,317us-gaap_RestructuringReserveCurrent
Non-current portion	92us-gaap_RestructuringReserveNoncurrent
Severance and restructuring accruals at end of period	2,401us-gaap_RestructuringReserve
Severance-related accruals
Restructuring Reserve [Roll Forward]
Balance as of September 30, 2014	1,317
Expense - charged to accrual	1,087
Payments and accrual adjustments	(647)
Balance as of March 31, 2015	1,757
Current portion	1,757
Non-current portion	0
Severance and restructuring accruals at end of period	1,757
Restructuring- related accruals
Restructuring Reserve [Roll Forward]
Balance as of September 30, 2014	0
Expense - charged to accrual	737
Payments and accrual adjustments	(93)
Balance as of March 31, 2015	644
Current portion	552
Non-current portion	92
Severance and restructuring accruals at end of period	$ 644

Restructuring Reserve, Settled With Cash and Accrual Adjustments

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

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-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

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- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

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