v3.10.0.1

MERGER Narrative (Details) - shares	3 Months Ended	6 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Jul. 20, 2018
Class of Stock [Line Items]
General partner ownership interest		2.00%
Common unit conversion rate			55.00%
Number of common limited partner units owned by general partner		10,214,626
Common Limited Partner [Member]
Class of Stock [Line Items]
Issuance of NuStar Energy common units as a result of the Merger, units issued	23,600,000
Issuance of NuStar Energy common units as a result of the Merger, incremental units issued	13,400,000

X

- Definition

Rate applied to the conversion of outstanding common units at the effective time of the merger (percent of acquirer's common unit to be exchanged per acquiree unit).

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- Definition

Conversion of Stock, Incremental Shares Issued

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- Definition

The general partner ownership interest (ownership percentage) in the limited partnership. Excludes other ownership interests held by the general partner in the limited partnership.

+ References

No definition available.

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X

- Definition

Number of Common Limited Partner Units Owned by General Partner

+ References

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- Definition

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.

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- Definition

The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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