Fair Value of Financial Instruments - Level 3 (Details) - Cross currency swaps - Level 3 - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Level 3 activity
Beginning balance:	$ 4,137		$ (18,630)
Unrealized gain on cross currency swaps	7,834		11,748
Ending balance:	$ 11,971	$ 4,137	$ (6,882)
Minimum
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	2.00%	6.10%
Maximum
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	3.00%	11.40%
Weighted average
Fair Value Measurements
Performance risk for derivative contracts as a percentage of unadjusted liabilities	2.70%	9.50%

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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