Derivative Financial Instruments (Schedule Of The Fair Values Of Derivative Instruments) (Details) - Cash flow hedging - Foreign currency - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivatives Designated as Hedging Instruments | Prepaid expenses and other current assets
Asset Derivatives
Derivative assets fair value	$ 708	$ 2,481
Derivatives Designated as Hedging Instruments | Accrued expenses and other current liabilities
Liability Derivatives
Derivative liabilities fair value	1,811	110
Derivatives Not Designated as Hedging Instruments | Prepaid expenses and other current assets
Asset Derivatives
Derivative assets fair value	56	17
Derivatives Not Designated as Hedging Instruments | Accrued expenses and other current liabilities
Liability Derivatives
Derivative liabilities fair value	$ 732	$ 704