CONVERTIBLE NOTES (Schedule of Interest Expense Recognized) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Loss on extinguishment of convertible notes	$ 831
Amortization of debt issuance costs and debt discount	2,673	$ 3,470	$ 2,991
2021 Notes
Contractual interest expense	2,855	4,344	4,344
Debt discount amortization	2,575	3,470	2,991
Loss on extinguishment of convertible notes	831
Other expenses		1,300
Total	6,261	$ 9,114	$ 7,335
2024 Notes
Contractual interest expense	767
Amortization of debt issuance costs and debt discount	97
Total	$ 864