Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments And Risk Management (Gross Notional Amount Of Outstanding Derivative Instruments) (Details)

v3.19.1
Financial Instruments And Risk Management (Gross Notional Amount Of Outstanding Derivative Instruments) (Details) - Currency Forward Contracts [Member] - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Mar. 31, 2018
Derivative Instruments Designated As Cash Flow Hedges [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Currency forward contracts $ 399,068 $ 399,348 $ 584,107
Derivative Instruments Not Designated As Cash Flow Hedges [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Currency forward contracts $ 208,941 $ 379,701 $ 234,579