EARNINGS PER COMMON UNIT (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net income (loss) attributable to the period	$ (764)	$ 7,946	$ (164,685)	$ 43,990
Less: net income allocated to participating securities	(2)	(27)	(26)	(90)
Net income (loss) attributable to common unitholders	$ (766)	$ 7,919	$ (164,711)	$ 43,900
Basic weighted average common units outstanding (in shares)	67,847,000	62,645,000	67,832,000	60,267,000
Effect of dilutive securities:
Effect of dilutive securities: Potential common units issuable (in shares)	0	33,000	0	29,000
Diluted weighted average common units outstanding (in shares)	67,847,000	62,678,000	67,832,000	60,296,000
Net income per common unit, basic (in USD per share)	$ (0.01)	$ 0.13	$ (2.43)	$ 0.73
Net income per common unit, diluted (in USD per share)	$ (0.01)	$ 0.13	$ (2.43)	$ 0.73
Anti-dilutive for potentially dilute basic earnings per common unit (in shares)	0		0