Fair Value Measurements (Details 2) (USD $)		12 Months Ended
Sep. 30, 2011	Sep. 30, 2010 Commodity contracts
Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Net derivatives, beginning balance		$ (3,237,000)
Transfers out of Level 3		3,237,000
Long-Term Debt
Carrying amount of total debt exclusive of capital leases	688,000,000
Fair market value	$ 746,000,000

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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-Subparagraph (SX 210.5-02.22)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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