v3.10.0.1

MERGER Narrative (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Jul. 20, 2018
Subsequent Events [Abstract] |  |  |  |  |  |
General partner ownership interest |  | 2.00% | 2.00% | 2.00% | 2.00% |
Number of common limited partner units owned by general partner |  | 10,214,626 |  | 10,214,626 |  |
Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Common unit conversion rate |  |  |  |  |  | 55.00%
Scenario, Forecast [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Assumed NSH Debt |  |  |  |  |  | $ 51.5
Merger, transaction costs |  |  |  |  |  | $ 10.0
Estimated effect of merger on net income per common unit | $ (3.55) |  |  |  |  |
Common Limited Partner [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [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 |  |  |  |  |

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- 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). + References No definition available. + Details
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- Definition Debt assumed in merger transaction + References No definition available. + Details
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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. + Details
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- Definition Number of Common Limited Partner Units Owned by General Partner + References No definition available. + Details
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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://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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- Details
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