Revenue Recognition (Schedule Of Contract Assets And Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Opening [Member]
Contract Receivables and Liabilities [Line Items]
Receivables	$ 19	$ 320	$ 326	$ 305
Contract Liabilities	722	214	663	219
Closing [Member]
Contract Receivables and Liabilities [Line Items]
Receivables	9	310	9	310
Contract Liabilities	2,193	242	2,193	242
Increase/(Decrease) [Member]
Contract Receivables and Liabilities [Line Items]
Receivables	(10)	(10)	(317)	5
Contract Liabilities	$ 1,471	$ 28	$ 1,530	$ 23