REDEEMABLE SERIES A PREFERRED STOCK - Securities Purchase Agreement (Details) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended	12 Months Ended
		Jun. 20, 2019	Mar. 07, 2019	Jul. 19, 2018	Jul. 31, 2018	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017	[2]	Mar. 06, 2019	Oct. 10, 2017
Class of Stock [Line Items]
Stock issued	[1]					$ 779
Aggregate cash proceeds on July 19, 2018						$ 9,110		$ 133,000	[2]	$ 0
Net carry value, end of period (shares)						155,231		141,000
Net carrying value, temporary equity						$ 131,316		$ 113,998	[3]
Net carrying value, common stock						$ 7		6	[3]
Liquidation preference (usd per share)			$ 1,000	$ 1,000		$ 10.00
Temporary equity, liquidation preference		$ 3,500	$ 6,500	$ 140,000		$ 155,231		140,846
Series A Preferred Stock
Class of Stock [Line Items]
Common stock issued (shares)				140,000	19,209
Common Stock
Class of Stock [Line Items]
Net carrying value, common stock													$ 3,900
Common stock issued (shares)		72,414	134,483	2,900,000		145,000	[4]
Shares issued, price per share (in usd per share)		$ 5.19		$ 6.95								$ 5.37
Private Placement
Class of Stock [Line Items]
Preferred stock issued		$ 2,997	$ 5,313	$ 126,763
Stock issued		3,373	6,035	146,894		$ 935	[1]	$ 17,593	[1]
Aggregate cash proceeds on July 19, 2018		3,325	5,785	133,000
Incremental and direct transaction costs		(339)	(751)	(4,628)
Net carrying value, common stock				$ 128,372
Net carrying value, Total		2,986	5,034
Incremental and direct costs, shares, cost		$ 200	$ 500
Private Placement | Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock issued (shares)		3,500	6,500	140,000
Preferred stock issued		$ 2,997	$ 5,313	$ 126,763
Aggregate cash proceeds on July 19, 2018		2,954	5,093	114,773
Incremental and direct transaction costs		$ (301)	$ (661)	$ (3,994)
Net carry value, end of period (shares)		3,500	6,500	140,000		155,231		140,846
Net carrying value, temporary equity		$ 2,653	$ 4,432	$ 110,779
Liquidation preference (usd per share)		$ 1,000
Private Placement | Common Stock
Class of Stock [Line Items]
Preferred stock issued				20,131
Stock issued		$ 376	722	20,131
Aggregate cash proceeds on July 19, 2018		371	692	18,227
Incremental and direct transaction costs		(38)	(90)	(634)
Net carrying value, temporary equity				17,593
Net carrying value, common stock		$ 333	$ 602
Common stock issued (shares)		72,414	134,483			207,000	[4]	2,897,000	[4]
Financial Advisor and Professional Fees | Private Placement
Class of Stock [Line Items]
Incremental and direct transaction costs				(2,700)
Due Diligence and Professional Fees | Private Placement
Class of Stock [Line Items]
Incremental and direct transaction costs		$ (200)	$ (300)	$ (1,900)

[1] See Note 3 for summary of adjustments.

[2] See Note 3 for summary of adjustments.

[3] See Note 3 for summary of adjustments

[4] See Note 1 for discussion of reverse recapitalization given effect herein.