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STOCK BASED COMPENSATION - Narrative (Details) - USD ($) $ in Millions				3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 01, 2019	Jan. 01, 2018	Jun. 21, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation				$ 0.3	$ 0.4	$ 0.5	$ 0.8
Compensation cost not yet recognized				$ 1.9		$ 1.9
Compensation cost not yet recognized (in years)						1 year 11 months
Expected dividend yield				0.00%	0.00%	0.00%	0.00%
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares authorized (in shares)	1,378,432	1,385,366	1,000,000
Percentage of outstanding stock								5.00%
Number of shares available for issuance (in shares)				2,859,590		2,859,590
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, aggregate intrinsic value				$ 0.6		$ 0.6