v3.10.0.1

MERGER Organizational structure before the Merger (Details) | 2 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2018 | Jun. 30, 2018 | Sep. 30, 2018
NuPOP | NuStar Energy |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest | 100.00% | 100.00% | 100.00%
NuStar Logistics | NuStar Energy |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest | 100.00% | 100.00% | 100.00%
Riverwalk Logistics, L.P. [Member] | NuStar GP, LLC [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest | 0.10% | 0.10% |
Riverwalk Logistics, L.P. [Member] | Riverwalk Holdings, LLC [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest | 99.90% | 99.90% |
NuStar Energy | Public Unitholders [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Common unitholders ownership interest | 100.00% | 89.00% |
NuStar Energy | NuStar GP, LLC [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest |  | 0.001% |
NuStar Energy | Riverwalk Holdings, LLC [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest |  | 11.00% |
NuStar GP, LLC [Member] | Nustar GP Holdings, LLC [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest | 100.00% | 100.00% |
Riverwalk Holdings, LLC [Member] | Nustar GP Holdings, LLC [Member] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |  |  |
Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest | 100.00% | 100.00% |

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