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Derivative Financial Instruments - Narrative (Details) - Derivatives designated as hedging instruments	3 Months Ended	6 Months Ended	12 Months Ended
	Sep. 30, 2018 USD ($) agreement	Mar. 31, 2019 USD ($)	Sep. 30, 2018 USD ($)
Interest rate swap agreements | Designated as cash flow hedges
Derivative Financial Instruments
Number of derivative agreements | agreement	5
Notional amount		$ 243,800,000
Fixed rate	2.79%		2.79%
Effective portion of interest rate swap agreements	$ (1,300,000)	5,500,000
Gain (loss) to be reclassified during next twelve months		1,000,000
Foreign currency forward contracts and interest rate swap agreements
Derivative Financial Instruments
Effective portion of interest rate swap agreements		(6,800,000)
Ineffective portion of derivative instruments		0	$ 0
Amounts excluded from effectiveness testing		$ 0	$ 0

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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X

- Definition

Represents the portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing the amount excluded from the assessment of hedge effectiveness.

+ References

No definition available.

+ Details

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- Definition

Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion

+ References

No definition available.

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- Definition

Represents the number of derivative agreements entered into by the entity during the reporting period.

+ References

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ 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

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994

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- Definition

Amount before tax of 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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