Intangible Assets (Schedule Of Amortization Expense For Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	$ 52	$ 51
Patents
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	50	43
Software
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	0	6
Marketing assets and customer relationships
Finite-Lived Intangible Assets [Line Items]
Total amortization expense	$ 2	$ 2