LOSS PER SHARE - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net loss	$ (14,130)	$ (5,628)	$ (20,576)	$ (8,805)
Less: Distributions to participating securities	0	0	0	(45)
Net loss attributable to common stockholders	$ (14,130)	$ (5,628)	$ (20,576)	$ (8,850)
Denominator:
Weighted-average shares outstanding (in shares)	67,094	56,568	67,161	57,556
Basic and diluted loss per share (in dollar per share)	$ (0.21)	$ (0.10)	$ (0.31)	$ (0.15)

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Amount of undistributed earnings (loss) allocated to participating securities for the basic earnings (loss) per share or per unit calculation under the two-class method.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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