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

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

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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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 foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 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
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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Derivative Instruments - Narrative (Details) - USD ($)	12 Months Ended
Derivative Instruments - Narrative (Details) - USD ($)	Sep. 30, 2018	Feb. 28, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Maximum length of time hedged in cash flow hedge	2 years
Net unrealized gains on cash flow hedges to be reclassified into earnings during the next 12 months	$ 5,700,000
Forward exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	1,030,400,000
Forward exchange contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	754,700,000
Forward exchange contracts \| Net Investment Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	81,000,000
Forward exchange contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	194,700,000
Interest rate swap contracts \| Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 600,000,000
Notes Payable Two and Three Total
Derivative Instruments, Gain (Loss) [Line Items]
Long-term debt		$ 600,000,000