CONVERTIBLE NOTES (Schedule Of Debt Interest Expenses) (Details) - Notes 2021 [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Contractual interest expense	$ 4,344	$ 4,344	$ 4,359
Debt discount amortization	3,470	2,991	2,587
Loss in connection with conversions			234
Loss in connection with conversions			245
Other expenses	1,300
Total	$ 9,114	$ 7,335	$ 7,425