EQUITY COMPENSATION (Phantom Units) (Details) - Phantom Shares $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($) $ / shares shares
Units
Balance at the beginning of the period (in units) \| shares	156,153
Vested (in units) \| shares	(70,352)
Forfeited (in units) \| shares	(16,200)
Balance at the end of the period (in units) \| shares	69,601
Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 19.00
Vested (in dollars per share)	19.00
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)	$ 20.7
Unrecognized compensation expenses \| $	$ 1.2
Weighted average period of compensation expense expected to be recognized	10 months 6 days
Cash used to settle awards \| $	$ 1.6

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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