Selected Balance Sheet Data (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Sep. 30, 2017
Accounts receivable, net:
Accounts receivable	$ 42,778	$ 31,365
Less allowance for doubtful accounts	566	341
Less reserve for future returns and pricing adjustments	2,423	2,169
Accounts receivable, net	39,789	28,855
Inventories:
Raw materials	24,804	24,050
Work in process	634	484
Finished goods	14,232	5,704
Inventories	$ 39,670	$ 30,238

Allowance for Future Returns and Pricing Adjustments

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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