Condensed Consolidated Statements of Stockholders Deficit - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2018		39,053,312
Beginning balance at Dec. 31, 2018	$ (13,124)	$ 39	$ 308,018	$ 32	$ (321,213)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(16,567)				(16,567)
Share-based compensation	379		379
Common stock sales (in shares)		9,374,597
Common stock issued	9,340	$ 9	9,331
Equity instrument exercises (in shares)		2,250
Equity instrument exercises	4		4
Other	(256)			(256)
Ending balance (in shares) at Sep. 30, 2019		48,430,159
Ending balance at Sep. 30, 2019	(20,224)	$ 48	317,732	(224)	(337,780)
Beginning balance (in shares) at Jun. 30, 2019		46,130,159
Beginning balance at Jun. 30, 2019	(16,899)	$ 46	315,829	65	(332,839)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(4,941)				(4,941)
Share-based compensation	65		65
Common stock sales (in shares)		2,300,000
Common stock issued	1,840	$ 2	1,838
Other	(289)			(289)
Ending balance (in shares) at Sep. 30, 2019		48,430,159
Ending balance at Sep. 30, 2019	$ (20,224)	$ 48	317,732	(224)	(337,780)
Beginning balance (in shares) at Dec. 31, 2019	51,055,159	51,055,159
Beginning balance at Dec. 31, 2019	$ (27,728)	$ 51	319,275	(227)	(346,827)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(7,825)				(7,825)
Share-based compensation	131		131
Common stock sales (in shares)		48,298,893
Common stock issued	32,030	$ 48	31,982
Equity instrument exercises (in shares)		148,364
Equity instrument exercises	142	$ 1	141
Other	$ 403			403
Ending balance (in shares) at Sep. 30, 2020	99,502,416	99,502,416
Ending balance at Sep. 30, 2020	$ (2,847)	$ 100	351,529	176	(354,652)
Beginning balance (in shares) at Jun. 30, 2020		99,408,916
Beginning balance at Jun. 30, 2020	(7,439)	$ 99	351,417	111	(359,066)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	4,414				4,414
Share-based compensation	38		38
Common stock issued	0
Equity instrument exercises (in shares)		93,500
Equity instrument exercises	75	$ 1	74
Other	$ 65			65
Ending balance (in shares) at Sep. 30, 2020	99,502,416	99,502,416
Ending balance at Sep. 30, 2020	$ (2,847)	$ 100	$ 351,529	$ 176	$ (354,652)