Financial Instruments And Risk Management (Gross Notional Amount Of Outstanding Derivative Instruments) (Details) - USD ($) $ in Thousands  | 
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2020  | 
Dec. 31, 2019  | 
Mar. 31, 2019  | 
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| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |||
| Derivative, Remaining Maturity | 4 years | ||
| Derivative Instruments Designated As Cash Flow Hedges [Member] | Currency Forward Contracts [Member] | |||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |||
| Currency forward contracts | $ 458,823 | $ 471,822 | $ 399,068 | 
| Derivative Instruments Not Designated As Cash Flow Hedges [Member] | Currency Forward Contracts [Member] | |||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |||
| Currency forward contracts | $ 205,030 | $ 214,086 | $ 208,941 | 
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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