INCOME TAXES - Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income tax expense
Current income taxes	$ 0	$ 0	$ 0	$ 0
Deferred income taxes	0	0	0	0
Losses before taxes	$ (18,036)	$ (10,305)	$ (33,970)	$ (17,788)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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