Derivative Instruments and Hedging Activities (Impact of Derivative Instruments on Earnings) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	$ (3,702)	$ 1,330	$ (32,484)
Amount of (Gain) Loss Recognized in Accumulated OCI on Derivative	1,672	18,262	(47,759)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	(3,702)	2,134	(31,446)
Floating-Rate Cross Currency Interest Rate Contract [Member] \| Derivatives in Fair Value Hedging Relationships [Member] \| Selling, General and Administrative Expenses [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	23	4,592	(9,394)
Amount of (Gain) Loss Recognized in Accumulated OCI on Derivative	60	4,832	(8,317)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	23	5,396	(8,356)
Fixed-Rate Cross Currency Interest Rate Contract [Member] \| Cash Flow Hedging \| Selling, General and Administrative Expenses [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative	(3,725)	(3,190)	(23,018)
Amount of (Gain) Loss Recognized in Accumulated OCI on Derivative	1,612	13,430	(39,442)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings	$ (3,725)	(3,190)	(23,018)
Treasury Lock \| Cash Flow Hedging \| Interest Expense
Derivative Instruments Gain Loss [Line Items]
Amount of (Income) Expense Recognized in Earnings on Derivative		(72)	(72)
Amount of (Gain) Loss Reclassified from Accumulated OCI into Earnings		$ (72)	$ (72)

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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