Accrued Expenses and Other Current Liabilities (Schedule of Product Warranty Accruals) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2014
Schedule of Product Warranty Accruals [Abstract]
Balance at beginning of period	$ 2,435us-gaap_ProductWarrantyAccrual	$ 3,663us-gaap_ProductWarrantyAccrual	$ 2,816us-gaap_ProductWarrantyAccrual	$ 3,881us-gaap_ProductWarrantyAccrual
Provision for product warranty - expense	113	1,296	515	1,296
Adjustments and utilization of warranty accrual	(624)	(230)	(1,407)	(448)
Balance at end of period	1,924us-gaap_ProductWarrantyAccrual	4,729us-gaap_ProductWarrantyAccrual	1,924us-gaap_ProductWarrantyAccrual	4,729us-gaap_ProductWarrantyAccrual
Current portion	1,723	4,198	1,723	4,198	2,285
Non-current portion	$ 201	$ 531	$ 201	$ 531

Product Warranty Accrual, Adjustments and Utilization of Accrual

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

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Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

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