INCOME (LOSS) PER COMMON SHARE - Summary of computation of basic and diluted net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net loss	$ (272,121)	$ (4,143)
Dividends on preferred stock	(25,397)	(10,687)
Unallocated net loss	(297,518)	(14,830)
Numerator for basic loss per share:
Net loss attributable to common stockholders	$ (297,518)	$ (14,830)
Denominator for basic loss per share:
Basic weighted average common shares outstanding (in shares)	87,912,362	62,854,214
Net loss per share:
Basic attributable to common stockholders (in dollars per share)	$ (3.38)	$ (0.24)
Numerator for diluted loss per share:
Net loss attributable to common stockholders	$ (297,518)	$ (14,830)
Add: interest expense on convertible Second Lien Term Loan	0	13,429
Less: gain on fair value change of embedded derivatives associated with Second Lien Term Loan	0	(35,471)
Net loss attributable to common stockholders	$ (297,518)	$ (36,872)
Denominator for diluted net loss per share:
Basic weighted average common shares outstanding (in shares)	87,912,362	62,854,214
Dilution effect of if-converted Second Lien Loans (in shares)	0	15,597,127
Diluted weighted average common shares outstanding (in shares)	87,912,362	78,451,341
Common shares (diluted) (in dollars per share)	$ (3.38)	$ (0.47)