Fair Value of Financial Instruments (Details 2) (Cross currency swaps, Level 3, USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2014
Level 3 activity
Beginning balance:	$ (18,630)	$ (22,254)
Unrealized gain (loss) on cross currency swaps	11,748	(5,105)
Ending balance:	$ (6,882)	$ (27,359)
Minimum
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	14.40%		8.10%
Maximum
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	16.70%		8.50%
Weighted average
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	15.00%		8.30%

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

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- Details

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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

+ Details

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