Fair Value of Financial Instruments (Details 2) - Cross currency swaps - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Level 3 activity
Beginning balance:	$ (18,630)	$ (22,254)
Unrealized gain on cross currency swaps	22,767	3,624
Ending balance:	$ 4,137	$ (18,630)
Minimum \| Level 3
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	6.10%	8.10%
Maximum \| Level 3
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	11.40%	8.50%
Weighted average \| Level 3
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	9.50%	8.30%

Represents the performance risk for derivative contracts as a percentage of unadjusted liabilities.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

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

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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

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