v3.8.0.1

PARTNERS' EQUITY (Tables) | 12 Months Ended
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Dec. 31, 2017
Distributions Made to Limited Partners and General Partner [Line Items] |
Schedule of Preferred Units [Table Text Block] | The following is a summary of our fixed-to-floating rate cumulative redeemable perpetual preferred units issued and outstanding as of December 31, 2017:
Units |  | Original Issuance Date |  | Number of Units Issued and Outstanding |  | Price per Unit |  | Net Proceeds (in millions) |  | Fixed Distribution Rate per Annum (as a Percentage of the $25.00 Liquidation Preference per Unit) |  | Fixed Distribution Rate per Unit per Annum |  | Optional Redemption Date/Date at Which Distribution Rate Becomes Floating |  | Floating Annual Rate (as a Percentage of the $25.00 Liquidation Preference per Unit)
Series A Preferred Units |  | November 25, 2016 |  | 9,060,000 |  | $ | 25.00 |  |  | $ | 218.4 |  |  | 8.50 | % |  | $ | 2.125 |  |  | December 15, 2021 |  | Three-month LIBOR plus 6.766%
Series B Preferred Units |  | April 28, 2017 |  | 15,400,000 |  | $ | 25.00 |  |  | $ | 371.8 |  |  | 7.625 | % |  | $ | 1.90625 |  |  | June 15, 2022 |  | Three-month LIBOR plus 5.643%
Series C Preferred Units |  | November 30, 2017 |  | 6,900,000 |  | $ | 25.00 |  |  | $ | 166.7 |  |  | 9.00 | % |  | $ | 2.25 |  |  | December 15, 2022 |  | Three-month LIBOR plus 6.88%
The following table summarizes financial information related to our preferred units:
| Preferred Limited Partners |  |
| Series A |  | Series B |  | Series C |  | Total
Balance as of January 1, 2016 | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Issuance of units | 218,400 |  |  | — |  |  | — |  |  | 218,400 |
Net income | 1,925 |  |  | — |  |  | — |  |  | 1,925 |
Distributions to partners | (1,925 | ) |  | — |  |  | — |  |  | (1,925 | )
Balance as of December 31, 2016 | 218,400 |  |  | — |  |  | — |  |  | 218,400 |
Issuance of units | — |  |  | 371,823 |  |  | 166,737 |  |  | 538,560 |
Net income | 19,253 |  |  | 19,815 |  |  | 1,380 |  |  | 40,448 |
Distributions to partners | (19,253 | ) |  | (19,815 | ) |  | (1,380 | ) |  | (40,448 | )
Other | (93 | ) |  | (189 | ) |  | (75 | ) |  | (357 | )
Balance as of December 31, 2017 | $ | 218,307 |  |  | $ | 371,634 |  |  | $ | 166,662 |  |  | $ | 756,603 |
Schedule of Calculation of Net Income Applicable to General Partner [Table Text Block] | The following table details the calculation of net income applicable to the general partner:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (Thousands of Dollars)
Net income attributable to NuStar Energy L.P. | $ | 147,964 |  |  | $ | 150,003 |  |  | $ | 306,720 |
Less preferred limited partner interest | 40,448 |  |  | 1,925 |  |  | — |
Less general partner incentive distribution | 45,669 |  |  | 43,407 |  |  | 43,220 |
Net income after general partner incentive distribution and preferred limited partner interest | 61,847 |  |  | 104,671 |  |  | 263,500 |
General partner interest allocation | 2 | % |  | 2 | % |  | 2 | %
General partner interest allocation of net income | 1,237 |  |  | 2,091 |  |  | 5,270 |
General partner incentive distribution | 45,669 |  |  | 43,407 |  |  | 43,220 |
Net income applicable to general partner | $ | 46,906 |  |  | $ | 45,498 |  |  | $ | 48,490 |
Schedule of Distribution Waterfall [Table Text Block] | Our available cash is distributed based on the percentages shown below:
|  | Percentage of Distribution
Quarterly Distribution Amount per Common Unit |  | Common Unitholders |  | General Partner Including Incentive Distributions
Up to $0.60 |  | 98% |  | 2%
Above $0.60 up to $0.66 |  | 90% |  | 10%
Above $0.66 |  | 75% |  | 25%
Schedule of Distributions To General and Common Limited Partners [Table Text Block] | The following table reflects the allocation of total cash distributions to the general partner and common limited partners applicable to the period in which the distributions were earned:
| Year Ended December 31,
| 2017 |  | 2016 |  | 2015
| (Thousands of Dollars, Except Per Unit Data)
General partner interest | $ | 9,252 |  |  | $ | 7,877 |  |  | $ | 7,844 |
General partner incentive distribution | 45,669 |  |  | 43,407 |  |  | 43,220 |
Total general partner distribution | 54,921 |  |  | 51,284 |  |  | 51,064 |
Common limited partners’ distribution | 407,681 |  |  | 342,598 |  |  | 341,140 |
Total cash distributions | $ | 462,602 |  |  | $ | 393,882 |  |  | $ | 392,204 |
Cash distributions per unit applicable to common limited partners | $ | 4.38 |  |  | $ | 4.38 |  |  | $ | 4.38 |
Distributions Made To Common Limited And General Partners By Distribution [Table Text Block] | The following table summarizes information related to our quarterly cash distributions to our general partner and common limited partners:
Quarter Ended |  | Cash Distributions Per Unit |  | Total Cash Distributions |  | Record Date |  | Payment Date
|  |  |  | (Thousands of Dollars) |  |  |  |
December 31, 2017 (a) |  | $ | 1.095 |  |  | $ | 115,267 |  |  | February 8, 2018 |  | February 13, 2018
September 30, 2017 |  | $ | 1.095 |  |  | $ | 115,084 |  |  | November 9, 2017 |  | November 14, 2017
June 30, 2017 |  | $ | 1.095 |  |  | $ | 115,083 |  |  | August 7, 2017 |  | August 11, 2017
March 31, 2017 |  | $ | 1.095 |  |  | $ | 117,168 |  |  | May 8, 2017 |  | May 12, 2017
(a) | The distribution was announced on January 29, 2018.
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] | The balance of and changes in the components included in “Accumulated other comprehensive income (loss)” were as follows:
| Foreign Currency Translation |  | Cash Flow Hedges |  | Pension and Other Postretirement Benefits |  | Total
| (Thousands of Dollars)
Balance as of January 1, 2015 | $ | (28,839 | ) |  | $ | (39,073 | ) |  | $ | — |  |  | $ | (67,912 | )
Other comprehensive (loss) income before reclassification adjustments | (31,987 | ) |  | 1,303 |  |  | — |  |  | (30,684 | )
Net loss on cash flow hedges reclassified into interest expense, net | — |  |  | 9,802 |  |  | — |  |  | 9,802 |
Other comprehensive (loss) income | (31,987 | ) |  | 11,105 |  |  | — |  |  | (20,882 | )
Balance as of December 31, 2015 | (60,826 | ) |  | (27,968 | ) |  | — |  |  | (88,794 | )
Employee Transfer | — |  |  | — |  |  | 4,201 |  |  | 4,201 |
Deferred income tax adjustments | — |  |  | — |  |  | 2,414 |  |  | 2,414 |
Other comprehensive loss before reclassification adjustments | (8,243 | ) |  | (2,621 | ) |  | (7,852 | ) |  | (18,716 | )
Net gain on pension costs reclassified into operating expense | — |  |  | — |  |  | (1,200 | ) |  | (1,200 | )
Net gain on pension costs reclassified into general and administrative expense | — |  |  | — |  |  | (413 | ) |  | (413 | )
Net loss on cash flow hedges reclassified into interest expense, net | — |  |  | 8,331 |  |  | — |  |  | 8,331 |
Other comprehensive (loss) income | (8,243 | ) |  | 5,710 |  |  | (2,850 | ) |  | (5,383 | )
Balance as of December 31, 2016 | (69,069 | ) |  | (22,258 | ) |  | (2,850 | ) |  | (94,177 | )
Other comprehensive income (loss) before reclassification adjustments | 17,466 |  |  | (8,670 | ) |  | (4,641 | ) |  | 4,155 |
Net gain on pension costs reclassified into operating expense | — |  |  | — |  |  | (1,143 | ) |  | (1,143 | )
Net gain on pension costs reclassified into general and administrative expense | — |  |  | — |  |  | (386 | ) |  | (386 | )
Net loss on cash flow hedges reclassified into interest expense, net | — |  |  | 6,624 |  |  | — |  |  | 6,624 |
Other comprehensive income (loss) | 17,466 |  |  | (2,046 | ) |  | (6,170 | ) |  | 9,250 |
Balance as of December 31, 2017 | $ | (51,603 | ) |  | $ | (24,304 | ) |  | $ | (9,020 | ) |  | $ | (84,927 | )
Preferred Limited Partner [Member] |
Distributions Made to Limited Partners and General Partner [Line Items] |
Distributions Made to Limited Partner, by Distribution [Table Text Block] | Preferred Units. The following table summarizes information related to our quarterly cash distributions on our Preferred Units:
Period |  | Cash Distributions Per Unit |  | Total Cash Distributions |  | Record Date |  | Payment Date
|  |  |  | (Thousands of Dollars) |  |  |  |
Series A Preferred Units: |  |  |  |  |  |  |  |
December 15, 2017 - March 14, 2018 (a) |  | $ | 0.53125 |  |  | $ | 4,813 |  |  | March 1, 2018 |  | March 15, 2018
September 15, 2017 - December 14, 2017 |  | $ | 0.53125 |  |  | $ | 4,813 |  |  | December 1, 2017 |  | December 15, 2017
June 15, 2017 - September 14, 2017 |  | $ | 0.53125 |  |  | $ | 4,813 |  |  | September 1, 2017 |  | September 15, 2017
March 15, 2017 - June 14, 2017 |  | $ | 0.53125 |  |  | $ | 4,813 |  |  | June 1, 2017 |  | June 15, 2017
November 25, 2016 - March 14, 2017 |  | $ | 0.64930556 |  |  | $ | 5,883 |  |  | March 1, 2017 |  | March 15, 2017
Series B Preferred Units: |  |  |  |  |  |  |  |
December 15, 2017 - March 14, 2018 (a) |  | $ | 0.47657 |  |  | $ | 7,339 |  |  | March 1, 2018 |  | March 15, 2018
September 15, 2017 - December 14, 2017 |  | $ | 0.47657 |  |  | $ | 7,339 |  |  | December 1, 2017 |  | December 15, 2017
April 28, 2017 - September 14, 2017 |  | $ | 0.725434028 |  |  | $ | 11,172 |  |  | September 1, 2017 |  | September 15, 2017
Series C Preferred Units: |  |  |  |  |  |  |  |
November 30, 2017 - March 14, 2018 (a) |  | $ | 0.65625 |  |  | $ | 4,528 |  |  | March 1, 2018 |  | March 15, 2018
(a) | The distribution was announced on January 29, 2018

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