Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Sep. 30, 2014
Liabilities
Long-term debt, amortized cost	$ 1,810,156us-gaap_DebtAndCapitalLeaseObligations	$ 1,811,641us-gaap_DebtAndCapitalLeaseObligations
Fair value measurement on recurring basis \| Total
Assets
Cash equivalents (a)	148,503	27,000
Total assets	150,837	27,511
Liabilities
Long-term debt (c)	1,911,303	1,874,444
Total liabilities	1,911,406	1,874,491
Fair value measurement on recurring basis \| Foreign exchange contracts \| Total
Assets
Foreign exchange contracts (b)	2,334	511
Liabilities
Foreign exchange contracts (b)	103	47
Fair value measurement on recurring basis \| Level 1
Assets
Cash equivalents (a)	148,503	27,000
Total assets	148,503	27,000
Liabilities
Long-term debt (c)	1,908,125	1,870,250
Total liabilities	1,908,125	1,870,250
Fair value measurement on recurring basis \| Level 2
Assets
Total assets	2,334	511
Liabilities
Long-term debt (c)	3,178	4,194
Total liabilities	3,281	4,241
Fair value measurement on recurring basis \| Level 2 \| Foreign exchange contracts
Assets
Foreign exchange contracts (b)	2,334	511
Liabilities
Foreign exchange contracts (b)	$ 103	$ 47

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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