Derivative Instruments and Hedging Activities (Fair Value Of Outstanding Designated And Undesignated Derivative Assets And Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	$ 8,331	$ 3,649
Other Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	114	551
Cash flow derivatives
Derivatives, Fair Value [Line Items]
Derivative assets	731	73
Designated hedge derivatives | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	8,085	3,572
Designated hedge derivatives | Other Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	114	551
Designated hedge derivatives | Cash flow derivatives | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	731	73
Designated hedge derivatives | Cash flow derivatives | Other Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	114	551
Designated hedge derivatives | Interest rate swaps | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	7,354	3,499
Designated hedge derivatives | Interest rate swaps | Other Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	0	0
Hedge derivatives not designated | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	246	77
Hedge derivatives not designated | Other Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 0	$ 0