v3.20.4

PARTNERS' EQUITY Narrative 2 (Details) - USD ($) $ / shares in Units, $ in Thousands			6 Months Ended	9 Months Ended	12 Months Ended
	Nov. 26, 2019	Jun. 29, 2018	Jun. 30, 2018	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Proceeds from issuance of common units, including contributions from general partner	$ 15,000				$ 0	$ 15,000	$ 10,204
Proceeds from common unit issuance including general partner contribution		$ 10,200
General partner ownership interest			2.00%
Common Limited Partner [Member]
Class of Stock [Line Items]
Issuance of units (units)	527,426	413,736			0	527,426	413,736
Units issued, price per unit	$ 28.44	$ 24.17
Issuance of NuStar Energy common units as a result of the Merger, incremental units issued				13,400,000	0	0	13,409,593
General Partner [Member]
Class of Stock [Line Items]
Proceeds from general partner contribution				$ 200
General partner ownership interest			2.00%

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Conversion of Stock, Incremental Shares Issued

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Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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The cash inflow from the issuance of common limited partners units during the period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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The cash inflow from the capital received in cash from a partner in a partnership during the period.

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-Topic 230
-SubTopic 10
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Per share or per unit amount of equity securities issued.

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