Components of Other Selected Captions in the Consolidated Balance Sheets (Detail) (USD $) In Thousands	Sep. 30, 2011	Sep. 30, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 77,318	$ 92,764
Less allowance for doubtful accounts	617	491
Accounts receivable, net	$ 76,701	$ 92,273

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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

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

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- Definition

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

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

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- Definition

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.

+ References

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

-Publisher SEC

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