STOCKHOLDERS' EQUITY - Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	6 Months Ended
	Jun. 30, 2017	Aug. 10, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 19, 2017	Dec. 31, 2016
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in dollars per share)	$ 0.0001		$ 0.0001			$ 0.0001
Proceeds from common stock issuance			$ 10,385	$ 0
Underwriting Agreement
Subsidiary, Sale of Stock [Line Items]
Proceeds from common stock issuance	$ 10,400
Common stock | Underwriting Agreement
Subsidiary, Sale of Stock [Line Items]
New share issues (in shares)	3,600,000
Price per share (in dollars per share)	$ 3.15		$ 3.15
Price per share, net proceeds (in dollars per share)	$ 2.90		2.90
Common stock | Over-allotment option
Subsidiary, Sale of Stock [Line Items]
New share issues (in shares)	540,000
Common Stock Warrant
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in dollars per share)	$ 0.0001		$ 0.0001
Soryn HLDR | Common Stock Warrant
Subsidiary, Sale of Stock [Line Items]
Exercise price (in dollars per share)					$ 3.18
Soryn HLDR | Common Stock Warrant | Common stock
Subsidiary, Sale of Stock [Line Items]
Number of shares called by warrant	2,300,000		2,300,000		2,000,000
Subsequent Event | Soryn HLDR | Common Stock Warrant
Subsidiary, Sale of Stock [Line Items]
Exercise price (in dollars per share)		$ 3.18
Subsequent Event | Soryn HLDR | Common Stock Warrant | Common stock | Over-allotment option
Subsidiary, Sale of Stock [Line Items]
Number of share called by warrant, increase		50,000