Receivables (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Sep. 30, 2011
Receivables Disclosure [Abstract]
Customer Concentration Risk	8.00%	8.00%
Receivable Details [Abstract]
Trade Accounts Receivable	$ 254,517	$ 203,038
Other Receivables	18,387	15,404
Accounts Receivable, Gross	272,904	218,442
Allowance for Doubtful Accounts Receivable	(2,511)	(2,581)
Accounts Receivable, Net	$ 270,393	$ 215,861

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- Definition

No authoritative reference available.

+ References

No definition available.

+ Details

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- Definition

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

+ References

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

-Publisher SEC

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

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-Publisher SEC

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Carrying amounts due as of the balance sheet date from parties or arising from transactions not otherwise specified in the taxonomy.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

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