Commitments and Contingencies (Commitments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Commitments and Contingencies Disclosure [Abstract]
Aggregate rental expense for leases	$ 6,270	$ 6,362	$ 5,221
Minimum future payments under operating leases
2014	5,518
2015	4,682
2016	4,220
2017	2,684
2018	1,992
After 2018	1,301
Contractual obligations under suplly, storage and service agreements
2014	190,606
2015	105,317
2016	75,903
2017	56,152
2018	44,409
After 2018	$ 114,263

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Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

+ References

No definition available.

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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

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Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of the recorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

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Amount of the recorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

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Amount of the recorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year.

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Amount of the recorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

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Amount of the recorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

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Amount of the recorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

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