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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

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- 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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- 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. + Details
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- Definition Represents the number of derivative agreements entered into by the entity during the reporting period. + References No definition available. + Details
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- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
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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. + Details
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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 + Details
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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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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