EQUITY COMPENSATION (Phantom Units) (Details) - Phantom Shares	3 Months Ended
	Mar. 31, 2018 USD ($) $ / shares shares
Units
Balance at the beginning of the period (in units) | shares	156,153
Vested (in units) | shares	0
Forfeited (in units) | shares	(9,362)
Balance at the end of the period (in units) | shares	146,791
Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 19.00
Vested (in dollars per share)
Forfeited (in dollars per share)	19.00
Balance at the end of the period (in dollars per share)	19.00
Share price (USD per share)	$ 21.4
Unrecognized compensation expenses | $	$ 1,700,000
Weighted average period of compensation expense expected to be recognized	1 year 1 month 2 days
Cash used to settle awards | $	$ 0