Hedging Instruments (Schedule Of Fair Values And Balance Sheet Classifications Of Derivatives Designated As Hedging Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Hedging Liabilities, Total hedging instruments presented on the balance sheet	$ 117,222	$ 113,035
Hedging Liabilities, Gross amounts subject to master netting arrangements not offset on the balance sheet	815	477
Hedging Liabilities, Net amount	116,407	112,558
Cash Flow Hedges [Member]
Derivatives, Fair Value [Line Items]
Hedging Liabilities, Total hedging instruments presented on the balance sheet	7,741	6,468
Derivatives Designated As Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Hedging Assets, Gross amounts subject to master netting arrangements not offset on the balance sheet	815	477
Hedging Assets, Net amount	77
Derivatives Designated As Hedging Instruments [Member] \| Cash Flow Hedges [Member]
Derivatives, Fair Value [Line Items]
Hedging Assets, Total derivative instruments presented as cash flow hedges on the balance sheet	892	477
Foreign Currency Exchange Contracts [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Hedging Liabilities, Total hedging instruments presented on the balance sheet	7,249	6,468
Foreign Currency Exchange Contracts [Member] \| Other Long-Term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Hedging Liabilities, Total hedging instruments presented on the balance sheet	492
Foreign Currency Exchange Contracts [Member] \| Derivatives Designated As Hedging Instruments [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Hedging Assets, Total derivative instruments presented as cash flow hedges on the balance sheet	452	477
Foreign Currency Exchange Contracts [Member] \| Derivatives Designated As Hedging Instruments [Member] \| Other Long-Term Assets, Net [Member]
Derivatives, Fair Value [Line Items]
Hedging Assets, Total derivative instruments presented as cash flow hedges on the balance sheet	440
Foreign Currency Borrowings Designated As Net Investment Hedge On The Balance Sheet [Member] \| Long-term Debt [Member]
Derivatives, Fair Value [Line Items]
Hedging Liabilities, Total hedging instruments presented on the balance sheet	$ 109,481	$ 106,567

Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, offset against an obligation to return collateral.

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- Definition

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset, deducted from derivative assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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+ References

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-Publisher FASB
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Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset, deducted from derivative liabilities.

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