STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $) In Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Statement of Income and Comprehensive Income [Abstract]
Net Income	$ 11,533	$ 24	$ 59,220	$ 44,506
Net gains (losses) on cash flow hedging derivative instruments:
Net hedging gain (loss) arising during period	9	(148)	449	78
Reclassification adjustment for gains included in net income	(196)	(77)	(317)	(213)
Net unrealized (losses) gains on cash flow hedging derivative instruments	(187)	(225)	132	(135)
Defined benefit pension and other postretirement benefit plans:
Amortization of actuarial loss included in net periodic pension and postretirement benefit cost	107	98	320	295
Other Comprehensive (Loss) Income, Before Tax	(80)	(127)	452	160
Income Tax (Benefit) Expense Related to Items of Other Comprehensive (Loss) Income	(31)	(49)	174	62
Other Comprehensive (Loss) Income, Net of Tax	(49)	(78)	278	98
Comprehensive Income (Loss)	$ 11,484	$ (54)	$ 59,498	$ 44,604

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A5
-Appendix A

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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The net prior service cost or credit recognized in other comprehensive income that is a reclassification adjustment of other comprehensive income as a result of being recognized as a component of net periodic benefit cost for the period.

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Pre tax change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges, net of reclassifications into earnings during the period. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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This element represents Other Comprehensive Income (Loss), Before Tax, for the period. The pretax revenues, expenses, gains, and losses that under generally accepted accounting principles are included in comprehensive income, but excluded from net income. Includes the entity's proportionate share of an investee's equity adjustments for other comprehensive income.

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This element represents Other Comprehensive Income (Loss), Net of Tax, for the period. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

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Tax effect of the change in accumulated other comprehensive income, that is, the tax effect on items included in other comprehensive income during the period.

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Tax effect on reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

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Pre tax change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. Includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.

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