Revenue Recognition (Schedule Of Contract Assets And Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Opening [Member]
Contract Receivables and Liabilities [Line Items]
Receivables	$ 326	$ 305
Contract Liabilities	663	219
Closing [Member]
Contract Receivables and Liabilities [Line Items]
Receivables	19	320
Contract Liabilities	722	214
Increase/(Decrease) [Member]
Contract Receivables and Liabilities [Line Items]
Receivables	(307)	15
Contract Liabilities	$ 59	$ (5)