Derivative Financial Instruments (Schedule Of Contracts Designated As Hedged Instruments) (Details) - Designated as Hedging Instrument [Member] € in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019 EUR (€)	Dec. 31, 2018 EUR (€)	Mar. 31, 2019 CAD ($)	Dec. 31, 2018 CAD ($)
Canadian Dollars [Member]
Foreign Exchange Contracts [Line Items]
Foreign exchange contracts, Notional Amount | $			$ 4,157	$ 6,166
Derivative, Maturity Date	Aug. 01, 2019	Aug. 01, 2019
Euro [Member]
Foreign Exchange Contracts [Line Items]
Foreign exchange contracts, Notional Amount | €	€ 11,149	€ 10,710
Derivative, Maturity Date	Feb. 01, 2020	Feb. 01, 2020