Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Definition

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611443-123010

+ Details

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- Details

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- Details

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MERGER Organizational structure after the Merger (Details)		6 Months Ended
	Jul. 20, 2018	Jun. 30, 2018
Riverwalk Logistics, L.P. [Member] \| NuStar GP, LLC [Member]
Subsequent Event [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		0.10%
Riverwalk Logistics, L.P. [Member] \| NuStar GP, LLC [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	0.10%
Riverwalk Logistics, L.P. [Member] \| Riverwalk Holdings, LLC [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest		99.90%
Riverwalk Logistics, L.P. [Member] \| Riverwalk Holdings, LLC [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest	99.90%
Riverwalk Holdings, LLC [Member] \| Nustar GP Holdings, LLC [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest		100.00%
Riverwalk Holdings, LLC [Member] \| Nustar GP Holdings, LLC [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest	100.00%
NuStar GP, LLC [Member] \| Nustar GP Holdings, LLC [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest		100.00%
NuStar GP, LLC [Member] \| Nustar GP Holdings, LLC [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest	100.00%
NuPOP \| NuStar Energy
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest		100.00%
NuPOP \| NuStar Energy \| Subsequent Event [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest	100.00%
Nustar GP Holdings, LLC [Member] \| NuStar Energy \| Subsequent Event [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest	100.00%
NuStar Logistics \| NuStar Energy
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest		100.00%
NuStar Logistics \| NuStar Energy \| Subsequent Event [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest	100.00%
NuStar Energy \| Public Unitholders [Member]
Subsequent Event [Line Items]
Common unitholders ownership interest		89.00%
NuStar Energy \| Public Unitholders [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Common unitholders ownership interest	100.00%
NuStar Energy \| NuStar GP, LLC [Member]
Subsequent Event [Line Items]
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest		0.001%