RELATED PARTY TRANSACTIONS (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Blackstone and First Reserve [Member] \| Series B Units [Member]
Related Party Transaction [Line Items]
Distribution To Unitholders	$ 0	$ 0	$ 6,152,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration