Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Total revenues	$ 148	$ 111	$ 262	$ 220
General and administrative	3,098	3,285	7,075	6,209
Depreciation	96	66	175	132
Total costs and expenses	3,194	3,351	7,250	6,341
Operating loss	(3,046)	(3,240)	(6,988)	(6,121)
Interest expense, net	(1,674)	(4,303)	(5,246)	(8,537)
Interest income	1	69	23	122
Loss before income taxes	(4,719)	(7,474)	(24,605)	(14,733)
Income tax expense	(1)	(2)	(3)	(3)
Loss from equity-method investments	(73)	0	(699)	0
Net loss and comprehensive loss applicable to common stock	$ (4,793)	$ (7,476)	$ (25,307)	$ (14,736)
Basic and diluted net loss per common share (in dollars per share)	$ (0.14)	$ (0.28)	$ (0.77)	$ (0.57)
Basic and diluted weighted average shares outstanding (in shares)	34,798	26,479	32,955	25,906
Debt conversion expense			$ 0	$ (197)
Loss on extinguishment of debt			$ (12,394)	$ 0