EQUITY, SHARE-BASED COMPENSATION AND WARRANTS, Summary of Equity Activity (Details) - USD ($) $ in Thousands	3 Months Ended						6 Months Ended	9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	$ 31,198	$ 34,509	$ 23,711	$ 16,834	$ 14,895	$ 14,733	$ 23,711	$ 23,711	$ 14,733
Balance (in shares)			29,098,207				29,098,207	29,098,207
Sale of common stock and Prefunded Warrant, net of costs			$ 11,593
Exercise of Prefunded Warrant		10
Retirement of unvested shares	0
Common stock awards under equity incentive plans	282	219	364	141	148	245
Exercise of common stock warrants			1,980	5,320	3,928	1,755
Conversion of preferred stock into common stock			0
Exercise of common stock options	9	87	60	27
Retirement of shares received in settlement with the sellers of Golden Ridge	(1,027)
Other		32	28	18	23	75
Net loss	(3,326)	(3,659)	(3,227)	(1,627)	(2,160)	(1,913)		$ (10,212)	(5,700)
Balance	$ 27,136	31,198	34,509	20,713	16,834	14,895	$ 31,198	$ 27,136	20,713
Balance (in shares)	33,109,222							33,109,222
Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	$ 112	112	201	313	313	313	201	$ 201	313
Sale of common stock and Prefunded Warrant, net of costs			0
Exercise of Prefunded Warrant		0
Retirement of unvested shares	0
Common stock awards under equity incentive plans	0	0	0	0	0	0
Exercise of common stock warrants			0	0	0	0
Conversion of preferred stock into common stock			(89)
Exercise of common stock options	0	0	0	0
Retirement of shares received in settlement with the sellers of Golden Ridge	0
Other		0	0	0	0	0
Net loss	0	0	0	0	0	0
Balance	$ 112	$ 112	$ 112	$ 313	$ 313	$ 313	$ 112	$ 112	$ 313
Preferred Stock [Member] | Series G Preferred Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance (in shares)	225	225	405	630	630	630	405	405	630
Sale of common stock and Prefunded warrant, net of costs (in shares)			0
Exercise of Prefunded Warrant (in shares)		0
Retirement of unvested shares (in shares)	0
Common stock awards under equity incentive plans (in shares)	0	0	0	0	0	0
Exercise of common stock warrants (in shares)			0	0	0	0
Conversion of preferred stock into common stock (in shares)			(180)
Exercise of common stock options (in shares)	0	0	0	0
Retirement of shares received in settlement with the sellers of Golden Ridge (in shares)	0
Other (in shares)		0	0	0	0	0
Balance (in shares)	225	225	225	630	630	630	225	225	630
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	$ 311,201	$ 310,853	$ 296,739	$ 285,722	$ 281,623	$ 279,548	$ 296,739	$ 296,739	$ 279,548
Balance (in shares)	34,246,714	33,029,652	29,098,207	24,254,013	19,953,107	18,046,731	29,098,207	29,098,207	18,046,731
Sale of common stock and Prefunded Warrant, net of costs			$ 11,593
Sale of common stock and Prefunded warrant, net of costs (in shares)			3,046,668
Exercise of Prefunded Warrant		$ 10
Exercise of Prefunded Warrant (in shares)		1,003,344
Retirement of unvested shares	$ 0
Retirement of unvested shares (in shares)	(830,124)
Common stock awards under equity incentive plans	$ 282	$ 219	$ 364	$ 141	$ 148	$ 245
Common stock awards under equity incentive plans (in shares)	22,632	134,984	36,881	7,188	208,829	78,377
Exercise of common stock warrants			$ 1,980	$ 5,320	$ 3,928	$ 1,755
Exercise of common stock warrants (in shares)			600,000	2,799,392	4,092,077	1,827,999
Conversion of preferred stock into common stock			$ 89
Conversion of preferred stock into common stock (in shares)			170,818
Exercise of common stock options	$ 9	$ 87	$ 60	$ 27
Exercise of common stock options (in shares)	10,000	78,734	77,078	32,500
Retirement of shares received in settlement with the sellers of Golden Ridge	$ (1,027)
Retirement of shares received in settlement with the sellers of Golden Ridge (in shares)	(340,000)
Other		$ 32	$ 28	$ 18	$ 23	$ 75
Other (in shares)		0	0	0	0	0
Net loss	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Balance	$ 310,465	$ 311,201	$ 310,853	$ 291,228	$ 285,722	$ 281,623	$ 311,201	$ 310,465	$ 291,228
Balance (in shares)	33,109,222	34,246,714	33,029,652	27,093,093	24,254,013	19,953,107	34,246,714	33,109,222	27,093,093
Accumulated Deficit [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	$ (280,115)	$ (276,456)	$ (273,229)	$ (269,201)	$ (267,041)	$ (265,128)	$ (273,229)	$ (273,229)	$ (265,128)
Sale of common stock and Prefunded Warrant, net of costs			0
Exercise of Prefunded Warrant		0
Retirement of unvested shares	0
Common stock awards under equity incentive plans	0	0	0	0	0	0
Exercise of common stock warrants			0	0	0	0
Conversion of preferred stock into common stock			0
Exercise of common stock options	0	0	0	0
Retirement of shares received in settlement with the sellers of Golden Ridge	0
Other		0	0	0	0	0
Net loss	(3,326)	(3,659)	(3,227)	(1,627)	(2,160)	(1,913)
Balance	$ (283,441)	$ (280,115)	$ (276,456)	$ (270,828)	$ (269,201)	$ (267,041)	$ (280,115)	$ (283,441)	$ (270,828)