Derivative Instruments and Hedging Activities (Impact of Derivative Instruments on Earnings) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	$ (11,045)	$ (18)	$ (19,008)	$ (36)
Amount of Gain/Loss Recognized in Accumulated OCI on Derivative	(9,609)		(28,172)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	(10,895)	(18)	(18,721)	(36)
Floating-Rate Cross Currency Interest Rate Contract [Member] \| Selling, General and Administrative Expenses [Member] \| Derivatives in Fair Value Hedging Relationships [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	(3,033)		(5,422)
Amount of Gain/Loss Recognized in Accumulated OCI on Derivative	(3,030)		(5,535)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	(2,883)		(5,135)
Fixed-Rate Cross Currency Interest Rate Contract [Member] \| Selling, General and Administrative Expenses [Member] \| Derivatives in Cash Flow Hedging Relationships [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	(7,994)		(13,550)
Amount of Gain/Loss Recognized in Accumulated OCI on Derivative	(6,579)		(22,637)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	(7,994)		(13,550)
Treasury Lock [Member] \| Interest Expense [Member] \| Derivatives in Cash Flow Hedging Relationships [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	(18)	(18)	(36)	(36)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	$ (18)	$ (18)	$ (36)	$ (36)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

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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).

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