MERGER AND RELATED PARTY AGREEMENTS Narrative 2 (Details)	12 Months Ended
Dec. 31, 2019
NuStar GP, LLC [Member]
Related Party Transaction [Line Items]
Administrative fees, description	(the Amended GP Services Agreement), which provided that we furnish administrative services necessary to conduct the business of Holdings, and Holdings compensated us for these services for an annual fee of $1.0 million, subject to adjustment based on the annual merit increase percentage applicable to our employees for the most recently completed fiscal year and for changes in level of service. We terminated the Amended GP Services Agreement in conjunction with the Merger.

Description of the nature of payments to a managing member or general partner, affiliate of a managing member or general partner, or affiliate of a limited liability company (LLC) or limited partnership (LP) for administrative services provided to the LLC or LP, for example, but is not limited to, salaries, rent, or other overhead costs. Includes a description of the services performed and the amount reimbursed for such services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration