GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Reverse Stock Split, Pro Forma Presentation, and Initial Public Offering (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jul. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Class of Stock [Line Items]
Stock issued during the period (in shares)	2,907,490
Preferred Stock, Shares Outstanding (in shares)		0	0
Repayments of Lines of Credit		$ 0	$ 19,500	$ 25,000
Proceeds from issuances of common stock, net of issuance costs		$ 0	$ 0	$ 54,209
Underwriters [Member]
Class of Stock [Line Items]
Proceeds from issuances of common stock, net of issuance costs	$ 54,100
Investor [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, Issued for Services	9,219,248