| Condensed Consolidating Balance Sheets [Text Block] |
Condensed Consolidating Balance Sheets March 31, 2020 (Thousands of Dollars) | | | | | | | | | | | | | | | | | | | | | | | | | | NuStar Energy | | NuStar Logistics | | NuPOP | | Non-Guarantor Subsidiaries | | Eliminations | | Consolidated | Assets | | | | | | | | | | | | Cash and cash equivalents | $ | 251 |
| | $ | 1,666 |
| | $ | — |
| | $ | 15,777 |
| | $ | — |
| | $ | 17,694 |
| Receivables, net | — |
| | 29 |
| | — |
| | 149,142 |
| | (4,504 | ) | | 144,667 |
| Inventories | — |
| | 2,033 |
| | 4,919 |
| | 3,768 |
| | — |
| | 10,720 |
| Prepaid and other current assets | 216 |
| | 10,331 |
| | 634 |
| | 3,594 |
| | — |
| | 14,775 |
| Intercompany receivable | — |
| | 1,284,697 |
| | — |
| | 374,851 |
| | (1,659,548 | ) | | — |
| Total current assets | 467 |
| | 1,298,756 |
| | 5,553 |
| | 547,132 |
| | (1,664,052 | ) | | 187,856 |
| Property, plant and equipment, net | — |
| | 2,045,134 |
| | 605,311 |
| | 1,455,196 |
| | — |
| | 4,105,641 |
| Intangible assets, net | — |
| | 37,327 |
| | — |
| | 631,449 |
| | — |
| | 668,776 |
| Goodwill | — |
| | 50,453 |
| | 170,652 |
| | 559,748 |
| | — |
| | 780,853 |
| Investment in wholly owned subsidiaries | 2,628,960 |
| | 1,624,851 |
| | 942,556 |
| | 484,606 |
| | (5,680,973 | ) | | — |
| Other long-term assets, net | 103 |
| | 70,845 |
| | 32,329 |
| | 31,417 |
| | — |
| | 134,694 |
| Total assets | $ | 2,629,530 |
| | $ | 5,127,366 |
| | $ | 1,756,401 |
| | $ | 3,709,548 |
| | $ | (7,345,025 | ) | | $ | 5,877,820 |
| Liabilities, Mezzanine Equity and Partners’ Equity | | | | | | | | | | | | Accounts payable | $ | 5,817 |
| | $ | 22,459 |
| | $ | 6,300 |
| | $ | 39,456 |
| | $ | — |
| | $ | 74,032 |
| Short-term debt and current portion of finance leases | — |
| | 14,366 |
| | 426 |
| | 77 |
| | — |
| | 14,869 |
| Accrued interest payable | — |
| | 40,569 |
| | 6 |
| | 30 |
| | — |
| | 40,605 |
| Accrued liabilities | 1,054 |
| | 71,282 |
| | 8,266 |
| | 23,575 |
| | — |
| | 104,177 |
| Taxes other than income tax | — |
| | 4,531 |
| | 6,337 |
| | 2,365 |
| | (4,504 | ) | | 8,729 |
| Income tax payable | — |
| | 621 |
| | 2 |
| | 4,827 |
| | — |
| | 5,450 |
| Intercompany payable | 423,799 |
| | — |
| | 1,235,749 |
| | — |
| | (1,659,548 | ) | | — |
| Total current liabilities | 430,670 |
| | 153,828 |
| | 1,257,086 |
| | 70,330 |
| | (1,664,052 | ) | | 247,862 |
| Long-term debt, less current portion | — |
| | 3,305,258 |
| | 1,688 |
| | 67,801 |
| | — |
| | 3,374,747 |
| Deferred income tax liability | — |
| | 1,499 |
| | 10 |
| | 9,164 |
| | — |
| | 10,673 |
| Other long-term liabilities | — |
| | 63,851 |
| | 13,128 |
| | 72,908 |
| | — |
| | 149,887 |
| Series D preferred units | 586,837 |
| | — |
| | — |
| | — |
| | — |
| | 586,837 |
| Total partners’ equity | 1,612,023 |
| | 1,602,930 |
| | 484,489 |
| | 3,489,345 |
| | (5,680,973 | ) | | 1,507,814 |
| Total liabilities, mezzanine equity and partners’ equity | $ | 2,629,530 |
| | $ | 5,127,366 |
| | $ | 1,756,401 |
| | $ | 3,709,548 |
| | $ | (7,345,025 | ) | | $ | 5,877,820 |
|
Condensed Consolidating Balance Sheets December 31, 2019 (Thousands of Dollars) | | | | | | | | | | | | | | | | | | | | | | | | | | NuStar Energy | | NuStar Logistics | | NuPOP | | Non-Guarantor Subsidiaries | | Eliminations | | Consolidated | Assets | | | | | | | | | | | | Cash and cash equivalents | $ | 176 |
| | $ | 24 |
| | $ | — |
| | $ | 15,992 |
| | $ | — |
| | $ | 16,192 |
| Receivables, net | — |
| | 317 |
| | 4 |
| | 152,209 |
| | — |
| | 152,530 |
| Inventories | — |
| | 1,953 |
| | 4,821 |
| | 5,619 |
| | — |
| | 12,393 |
| Prepaid and other current assets | 61 |
| | 16,325 |
| | 600 |
| | 4,947 |
| | — |
| | 21,933 |
| Intercompany receivable | — |
| | 1,276,839 |
| | — |
| | 610,298 |
| | (1,887,137 | ) | | — |
| Total current assets | 237 |
| | 1,295,458 |
| | 5,425 |
| | 789,065 |
| | (1,887,137 | ) | | 203,048 |
| Property, plant and equipment, net | — |
| | 2,058,530 |
| | 612,128 |
| | 1,448,321 |
| | — |
| | 4,118,979 |
| Intangible assets, net | — |
| | 39,683 |
| | — |
| | 641,949 |
| | — |
| | 681,632 |
| Goodwill | — |
| | 149,453 |
| | 170,652 |
| | 685,748 |
| | — |
| | 1,005,853 |
| Investment in wholly owned subsidiaries | 2,871,540 |
| | 1,743,066 |
| | 1,155,855 |
| | 490,826 |
| | (6,261,287 | ) | | — |
| Other long-term assets, net | 98 |
| | 111,362 |
| | 32,121 |
| | 32,899 |
| | — |
| | 176,480 |
| Total assets | $ | 2,871,875 |
| | $ | 5,397,552 |
| | $ | 1,976,181 |
| | $ | 4,088,808 |
| | $ | (8,148,424 | ) | | $ | 6,185,992 |
| Liabilities, Mezzanine Equity and Partners’ Equity | | | | | | | | | | | | Accounts payable | $ | 5,427 |
| | $ | 42,064 |
| | $ | 8,379 |
| | $ | 53,964 |
| | $ | — |
| | $ | 109,834 |
| Short-term debt and current portion of finance leases | — |
| | 9,722 |
| | 299 |
| | 25 |
| | — |
| | 10,046 |
| Current portion of long-term debt | — |
| | 452,367 |
| | — |
| | — |
| | — |
| | 452,367 |
| Accrued interest payable | — |
| | 37,888 |
| | 4 |
| | 33 |
| | — |
| | 37,925 |
| Accrued liabilities | 1,425 |
| | 40,514 |
| | 8,461 |
| | 53,885 |
| | — |
| | 104,285 |
| Taxes other than income tax | 125 |
| | 7,311 |
| | 5,160 |
| | 185 |
| | — |
| | 12,781 |
| Income tax payable | — |
| | 492 |
| | 2 |
| | 3,831 |
| | — |
| | 4,325 |
| Intercompany payable | 438,857 |
| | — |
| | 1,448,280 |
| | — |
| | (1,887,137 | ) | | — |
| Total current liabilities | 445,834 |
| | 590,358 |
| | 1,470,585 |
| | 111,923 |
| | (1,887,137 | ) | | 731,563 |
| Long-term debt, less current portion | — |
| | 2,871,786 |
| | 1,127 |
| | 62,005 |
| | — |
| | 2,934,918 |
| Deferred income tax liability | — |
| | 1,499 |
| | 10 |
| | 10,918 |
| | — |
| | 12,427 |
| Other long-term liabilities | — |
| | 65,577 |
| | 13,774 |
| | 69,588 |
| | — |
| | 148,939 |
| Series D preferred units | 581,935 |
| | — |
| | — |
| | — |
| | — |
| | 581,935 |
| Total partners’ equity | 1,844,106 |
| | 1,868,332 |
| | 490,685 |
| | 3,834,374 |
| | (6,261,287 | ) | | 1,776,210 |
| Total liabilities, mezzanine equity and partners’ equity | $ | 2,871,875 |
| | $ | 5,397,552 |
| | $ | 1,976,181 |
| | $ | 4,088,808 |
| | $ | (8,148,424 | ) | | $ | 6,185,992 |
|
|
| Condensed Consolidating Statements of Comprehensive Income (Loss) [Table Text Block] |
Condensed Consolidating Statements of Comprehensive (Loss) Income For the Three Months Ended March 31, 2020 (Thousands of Dollars) | | | | | | | | | | | | | | | | | | | | | | | | | | NuStar Energy | | NuStar Logistics | | NuPOP | | Non-Guarantor Subsidiaries | | Eliminations | | Consolidated | Revenues | $ | — |
| | $ | 161,302 |
| | $ | 62,664 |
| | $ | 168,961 |
| | $ | (136 | ) | | $ | 392,791 |
| Costs and expenses | 728 |
| | 184,171 |
| | 37,779 |
| | 263,308 |
| | (136 | ) | | 485,850 |
| Operating (loss) income | (728 | ) | | (22,869 | ) | | 24,885 |
| | (94,347 | ) | | — |
| | (93,059 | ) | Equity in (loss) earnings of subsidiaries | (146,988 | ) | | (118,215 | ) | | 16,787 |
| | 41,579 |
| | 206,837 |
| | — |
| Interest income (expense), net | 75 |
| | (48,070 | ) | | (319 | ) | | 820 |
| | — |
| | (47,494 | ) | Other income (expense), net | — |
| | 859 |
| | 247 |
| | (7,595 | ) | | — |
| | (6,489 | ) | (Loss) income before income tax expense | (147,641 | ) | | (188,295 | ) | | 41,600 |
| | (59,543 | ) | | 206,837 |
| | (147,042 | ) | Income tax expense | — |
| | 129 |
| | — |
| | 470 |
| | — |
| | 599 |
| Net (loss) income | $ | (147,641 | ) | | $ | (188,424 | ) | | $ | 41,600 |
| | $ | (60,013 | ) | | $ | 206,837 |
| | $ | (147,641 | ) | | | | | | | | | | | | | Comprehensive (loss) income | $ | (147,641 | ) | | $ | (217,607 | ) | | $ | 41,600 |
| | $ | (67,143 | ) | | $ | 206,837 |
| | $ | (183,954 | ) |
Condensed Consolidating Statements of Comprehensive Loss For the Three Months Ended March 31, 2019 (Thousands of Dollars) | | | | | | | | | | | | | | | | | | | | | | | | | | NuStar Energy | | NuStar Logistics | | NuPOP | | Non-Guarantor Subsidiaries | | Eliminations | | Consolidated | Revenues | $ | — |
| | $ | 117,555 |
| | $ | 58,353 |
| | $ | 172,105 |
| | $ | (187 | ) | | $ | 347,826 |
| Costs and expenses | 676 |
| | 77,411 |
| | 36,050 |
| | 160,271 |
| | (187 | ) | | 274,221 |
| Operating (loss) income | (676 | ) | | 40,144 |
| | 22,303 |
| | 11,834 |
| | — |
| | 73,605 |
| Equity in earnings of subsidiaries | 29,491 |
| | 1,339 |
| | 12,738 |
| | 33,285 |
| | (76,853 | ) | | — |
| Interest income (expense), net | 108 |
| | (45,456 | ) | | (1,933 | ) | | 2,990 |
| | — |
| | (44,291 | ) | Other income (expense), net | — |
| | 754 |
| | 177 |
| | (140 | ) | | — |
| | 791 |
| Income (loss) from continuing operations before income tax expense | 28,923 |
| | (3,219 | ) | | 33,285 |
| | 47,969 |
| | (76,853 | ) | | 30,105 |
| Income tax expense | — |
| | 117 |
| | — |
| | 1,065 |
| | — |
| | 1,182 |
| Income (loss) from continuing operations | 28,923 |
| | (3,336 | ) | | 33,285 |
| | 46,904 |
| | (76,853 | ) | | 28,923 |
| Loss from discontinued
operations, net of tax (a) | (306,786 | ) | | — |
| | (306,786 | ) | | (613,572 | ) | | 920,358 |
| | (306,786 | ) | Net loss | $ | (277,863 | ) | | $ | (3,336 | ) | | $ | (273,501 | ) | | $ | (566,668 | ) | | $ | 843,505 |
| | $ | (277,863 | ) | | | | | | | | | | | | | Comprehensive loss | $ | (277,863 | ) | | $ | (9,066 | ) | | $ | (273,501 | ) | | $ | (565,764 | ) | | $ | 843,505 |
| | $ | (282,689 | ) |
(a) Includes equity in earnings (loss) of subsidiaries related to discontinued operations.
|
| Condensed Consolidating Statements of Cash Flows [Text Block] |
Condensed Consolidating Statements of Cash Flows For the Three Months Ended March 31, 2020 (Thousands of Dollars) | | | | | | | | | | | | | | | | | | | | | | | | | | NuStar Energy | | NuStar Logistics | | NuPOP | | Non-Guarantor Subsidiaries | | Eliminations | | Consolidated | Net cash provided by operating activities | $ | 94,676 |
| | $ | 64,365 |
| | $ | 265,236 |
| | $ | 100,630 |
| | $ | (373,479 | ) | | $ | 151,428 |
| Cash flows from investing activities: | | | | | | | | | | | | Capital expenditures | — |
| | (14,674 | ) | | (1,506 | ) | | (40,103 | ) | | — |
| | (56,283 | ) | Change in accounts payable related to capital expenditures | — |
| | (12,807 | ) | | (3,390 | ) | | 491 |
| | — |
| | (15,706 | ) | Proceeds from sale or disposition of assets | — |
| | 299 |
| | 48 |
| | 218 |
| | — |
| | 565 |
| Net cash used in investing activities | — |
| | (27,182 | ) | | (4,848 | ) | | (39,394 | ) | | — |
| | (71,424 | ) | Cash flows from financing activities: | | | | | | | | | | | | Debt borrowings | — |
| | 178,000 |
| | — |
| | 9,200 |
| | — |
| | 187,200 |
| Debt repayments | — |
| | (148,515 | ) | | — |
| | (3,600 | ) | | — |
| | (152,115 | ) | Distributions to preferred unitholders | (30,423 | ) | | (15,212 | ) | | (15,212 | ) | | (15,212 | ) | | 45,636 |
| | (30,423 | ) | Distributions to common unitholders | (65,169 | ) | | (32,584 | ) | | (32,584 | ) | | (32,589 | ) | | 97,757 |
| | (65,169 | ) | Distributions to affiliates | — |
| | — |
| | — |
| | (230,086 | ) | | 230,086 |
| | — |
| Net intercompany activity | 10,469 |
| | (10,246 | ) | | (212,484 | ) | | 212,261 |
| | — |
| | — |
| Payment of tax withholding for unit-based compensation | (8,820 | ) | | — |
| | — |
| | — |
| | — |
| | (8,820 | ) | Other, net | (658 | ) | | (6,974 | ) | | (108 | ) | | (22 | ) | | — |
| | (7,762 | ) | Net cash used in financing activities | (94,601 | ) | | (35,531 | ) | | (260,388 | ) | | (60,048 | ) | | 373,479 |
| | (77,089 | ) | Effect of foreign exchange rate changes on cash | — |
| | — |
| | — |
| | (1,403 | ) | | — |
| | (1,403 | ) | Net increase (decrease) in cash, cash equivalents and restricted cash | 75 |
| | 1,652 |
| | — |
| | (215 | ) | | — |
| | 1,512 |
| Cash, cash equivalents, and restricted cash as of the beginning of the period | 176 |
| | 8,812 |
| | — |
| | 15,992 |
| | — |
| | 24,980 |
| Cash, cash equivalents and restricted cash as of the end of the period | $ | 251 |
| | $ | 10,464 |
| | $ | — |
| | $ | 15,777 |
| | $ | — |
| | $ | 26,492 |
|
Condensed Consolidating Statements of Cash Flows For the Three Months Ended March 31, 2019 (Thousands of Dollars) | | | | | | | | | | | | | | | | | | | | | | | | | | NuStar Energy | | NuStar Logistics | | NuPOP | | Non-Guarantor Subsidiaries | | Eliminations | | Consolidated | Net cash provided by operating activities | $ | 93,209 |
| | $ | 26,732 |
| | $ | 11,953 |
| | $ | 113,864 |
| | $ | (142,190 | ) | | $ | 103,568 |
| Cash flows from investing activities: | | | | | | | | | | | | Capital expenditures | — |
| | (87,696 | ) | | (2,253 | ) | | (69,480 | ) | | — |
| | (159,429 | ) | Change in accounts payable related to capital expenditures | — |
| | 14,894 |
| | 15,532 |
| | (11,025 | ) | | — |
| | 19,401 |
| Proceeds from sale or disposition of assets | — |
| | 46 |
| | 1 |
| | 32 |
| | — |
| | 79 |
| Net cash (used in) provided by investing activities | — |
| | (72,756 | ) | | 13,280 |
| | (80,473 | ) | | — |
| | (139,949 | ) | Cash flows from financing activities: | | | | | | | | | | | | Debt borrowings | — |
| | 306,500 |
| | — |
| | 5,000 |
| | — |
| | 311,500 |
| Debt repayments | — |
| | (143,500 | ) | | — |
| | (14,600 | ) | | — |
| | (158,100 | ) | Distributions to preferred unitholders | (30,423 | ) | | (15,212 | ) | | (15,212 | ) | | (15,211 | ) | | 45,635 |
| | (30,423 | ) | Distributions to common unitholders | (64,367 | ) | | (32,183 | ) | | (32,183 | ) | | (32,189 | ) | | 96,555 |
| | (64,367 | ) | Net intercompany activity | 8,948 |
| | (55,453 | ) | | 22,164 |
| | 24,341 |
| | — |
| | — |
| Payment of tax withholding for unit-based compensation | (6,366 | ) | | — |
| | — |
| | — |
| | — |
| | (6,366 | ) | Other, net | (893 | ) | | (4,227 | ) | | (2 | ) | | (5 | ) | | — |
| | (5,127 | ) | Net cash (used in) provided by financing activities | (93,101 | ) | | 55,925 |
| | (25,233 | ) | | (32,664 | ) | | 142,190 |
| | 47,117 |
| Effect of foreign exchange rate changes on cash | — |
| | — |
| | — |
| | 154 |
| | — |
| | 154 |
| Net increase in cash, cash equivalents and restricted cash | 108 |
| | 9,901 |
| | — |
| | 881 |
| | — |
| | 10,890 |
| Cash, cash equivalents and restricted cash as of the beginning of the period | 1,255 |
| | 51 |
| | — |
| | 12,338 |
| | — |
| | 13,644 |
| Cash, cash equivalents and restricted cash as of the end of the period | $ | 1,363 |
| | $ | 9,952 |
| | $ | — |
| | $ | 13,219 |
| | $ | — |
| | $ | 24,534 |
|
|