CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (PARENTHETICAL) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent, Parenthetical Disclosures [Abstract]
Unrealized holding gains (losses) on available-for-sale securities, tax	$ (186)	$ 1,881	$ (953)
Amortization and unrealized gain (loss) on interest rate agreements, tax	47,236	(5,388)	(16,850)
Unrealized gains (losses) on commodity cash flow hedges, tax	$ 2,889	$ 5,029	$ 3,355

Tax effect on reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of interest rate agreements included in accumulated comprehensive income that was realized in net income during the period. Also includes tax effect on the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of interest rate agreements.

No definition available.

+ Details

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- Definition

Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e640-108580

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e640-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (e,f)

-URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580

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