Derivative Instruments and Hedging Activities (Impact of Derivative Instruments on Earnings) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	$ (22,649)	$ 6,566	$ (19,059)	$ (12,442)
Amount of (Gain) Loss Recognized in Accumulated OCI on Derivative	26,011	7,305	(7,993)	(20,867)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	(22,649)	6,890	(18,255)	(11,831)
Floating-Rate Cross Currency Interest Rate Contract [Member] \| Derivatives in Fair Value Hedging Relationships [Member] \| Selling, General and Administrative Expense [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	2,254	1,340	2,487	(4,082)
Amount of (Gain) Loss Recognized in Accumulated OCI on Derivative	718	2,315	2,793	(3,220)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	2,254	1,664	3,291	(3,471)
Fixed-Rate Cross Currency Interest Rate Contract [Member] \| Cash Flow Hedging \| Selling, General and Administrative Expense [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	(24,885)	5,244	(21,492)	(8,306)
Amount of (Gain) Loss Recognized in Accumulated OCI on Derivative	25,293	4,990	(10,786)	(17,647)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	(24,885)	5,244	(21,492)	(8,306)
Treasury Lock [Member] \| Cash Flow Hedging \| Interest Expense [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	(18)	(18)	(54)	(54)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	$ (18)	$ (18)	$ (54)	$ (54)

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

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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.

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Amount after 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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