Derivative Instruments and Hedging Activities (Schedule Of Derivative Instrument Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives Designated As Hedging Instruments Under ASC Topic 815
Derivatives, Fair Value [Line Items]
Notional Value	$ 676,639	$ 555,543
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Other Current Assets
Derivatives, Fair Value [Line Items]
Asset, Fair Value	1,388	28,705
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability, Fair Value	21,308	142
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Foreign currency contracts | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Notional Value	675,724	554,551
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Foreign currency contracts | Other Current Assets | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Asset, Fair Value	1,388	28,528
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Foreign currency contracts | Accrued Liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Liability, Fair Value	21,239	142
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Commodities contracts | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Notional Value	915	992
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Commodities contracts | Other Current Assets | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Asset, Fair Value	0	177
Derivatives Designated As Hedging Instruments Under ASC Topic 815 | Commodities contracts | Accrued Liabilities | Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Liability, Fair Value	69	0
Derivatives Not Designated As Hedging Instruments Under ASC Topic 815
Derivatives, Fair Value [Line Items]
Notional Value	4,532	5,025
Derivatives Not Designated As Hedging Instruments Under ASC Topic 815 | Other Current Assets
Derivatives, Fair Value [Line Items]
Asset, Fair Value	381	329
Derivatives Not Designated As Hedging Instruments Under ASC Topic 815 | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability, Fair Value	0	0
Derivatives Not Designated As Hedging Instruments Under ASC Topic 815 | Commodities contracts
Derivatives, Fair Value [Line Items]
Notional Value	4,532	5,025
Derivatives Not Designated As Hedging Instruments Under ASC Topic 815 | Commodities contracts | Other Current Assets
Derivatives, Fair Value [Line Items]
Asset, Fair Value	381	329
Derivatives Not Designated As Hedging Instruments Under ASC Topic 815 | Commodities contracts | Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability, Fair Value	$ 0	$ 0