v3.8.0.1

DEBT Narrative 2 (Details) - USD ($) |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jan. 15, 2018 | Apr. 28, 2017 | Mar. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Debt Instrument [Line Items] |  |  |  |  |  |
Proceeds from note offering, net of issuance costs |  |  |  | $ 543,333,000 | $ 0 | $ 0
Amount outstanding |  |  |  | 3,613,059,000 | 3,014,364,000 |
Short-term debt |  |  |  | $ 35,000,000 | 54,000,000 |
7.65% senior notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate |  |  |  | 7.65% |  |
Amount outstanding |  |  |  | $ 350,000,000 | $ 350,000,000 |
Interest rate terms |  |  |  | The interest rate payable on the 7.65% senior notes is subject to adjustment if our debt rating is downgraded (or upgraded) by certain credit rating agencies |  |
Effective interest rate |  |  |  | 8.40% | 8.15% |
Maturity Date |  |  |  | Mar. 15, 2018 |  |
5.625% senior notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Senior notes issued |  | $ 550,000,000 |  |  |  |
Stated interest rate |  | 5.625% |  | 5.625% |  |
Proceeds from note offering, net of issuance costs |  | $ 543,300,000 |  |  |  |
Amount outstanding |  |  |  | $ 550,000,000 | $ 0 |
Debt Instrument, Redemption, Description |  |  |  | If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes or the 5.625% senior notes, each holder of the 6.75% senior notes or the 5.625% senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes, plus any accrued and unpaid interest to the date of repurchase |  |
Maturity Date |  |  |  | Apr. 28, 2027 |  |
4.80% senior notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate |  |  |  | 4.80% |  |
Amount outstanding |  |  |  | $ 450,000,000 | 450,000,000 |
Maturity Date |  |  |  | Sep. 01, 2020 |  |
6.75% senior notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate |  |  |  | 6.75% |  |
Amount outstanding |  |  |  | $ 300,000,000 | 300,000,000 |
Debt Instrument, Redemption, Description |  |  |  | If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes or the 5.625% senior notes, each holder of the 6.75% senior notes or the 5.625% senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes, plus any accrued and unpaid interest to the date of repurchase |  |
Maturity Date |  |  |  | Feb. 01, 2021 |  |
4.75% senior notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate |  |  |  | 4.75% |  |
Amount outstanding |  |  |  | $ 250,000,000 | 250,000,000 |
Maturity Date |  |  |  | Feb. 01, 2022 |  |
7.625% subordinated notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated interest rate |  |  |  | 7.625% |  |
Amount outstanding |  |  |  | $ 402,500,000 | 402,500,000 |
Interest rate terms |  |  |  | The Subordinated Notes bore interest at a fixed annual rate of 7.625%, payable quarterly in arrears beginning on April 15, 2013 and ending on January 15, 2018. Thereafter, the Subordinated Notes bear interest at an annual rate equal to the sum of the three-month LIBOR rate for the related quarterly interest period, plus 6.734% payable quarterly, commencing April 15, 2018, unless payment is deferred in accordance with the terms of the notes. NuStar Logistics may elect to defer interest payments on the Subordinated Notes on one or more occasions for up to five consecutive years. |  |
Maturity Date |  |  |  | Jan. 15, 2043 |  |
Gulf Opportunity Zone revenue bonds |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount outstanding |  |  |  | $ 365,440,000 | 365,440,000 |
Amount Received From Trustee |  |  |  | 0 | 12,500,000 |
Amended Receivables Financing Agreement |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount outstanding |  |  |  | $ 62,300,000 | 58,400,000 |
Maturity Date |  |  |  | Sep. 20, 2020 |  |
Maximum borrowing capacity |  |  |  | $ 125,000,000 |  |
Line of Credit Facility, Borrowing Capacity, Description |  |  |  | The maximum amount available for borrowing by NuStar Finance under the Receivables Financing Agreement is $125.0 million, with an option for NuStar Finance to request an increase of up to $75.0 million from the lenders (for aggregate total borrowings not to exceed $200.0 million). The amount available for borrowing is based on the availability of eligible receivables and other customary factors and conditions. |  |
Debt Instrument, Maturity Date, Description |  |  |  | On September 20, 2017, the Securitization Program was amended to add certain of NuStar Energy’s wholly owned subsidiaries resulting from the Navigator Acquisition and to extend the Securitization Program’s scheduled termination date from June 15, 2018 to September 20, 2020, with the option to renew for additional 364-day periods thereafter. |  |
Debt Instrument, Collateral Amount |  |  |  | $ 92,600,000 | $ 104,500,000 |
Average Annual Interest Rate |  |  |  | 2.00% |  |
Short-term lines of credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Maximum borrowing capacity |  |  |  | $ 85,000,000 |  |
Average Annual Interest Rate |  |  |  | 2.70% | 2.00% |
Short-term debt |  |  |  | $ 35,000,000 |  |
Subsequent Event [Member] | 7.65% senior notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Effective interest rate |  |  | 8.65% |  |  |
Interest rate increase |  |  | 0.25% |  |  |
Subsequent Event [Member] | 7.625% subordinated notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Redemption Price, Percentage | 100.00% |  |  |  |  |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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