CONDENSED CONSOLIDATING FINANCIAL STATEMENTS Table 3 - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net cash provided by operating activities	$ 270,441	$ 240,894
Cash flows from investing activities:
Capital expenditures	(96,358)	(319,961)
Change in accounts payable related to capital expenditures	(15,509)	16,144
Proceeds from sale or disposition of assets	5,787	143
Investment in subsidiaries		0
Net cash (used in) provided by investing activities	(106,080)	(303,674)
Cash flows from financing activities:
Debt borrowings	842,035	594,300
Proceeds from note offering, net of issuance costs	0	491,665
Debt repayments	(762,215)	(807,800)
Distributions to preferred unitholders	(60,846)	(60,846)
Distributions to common unitholders	(108,846)	(129,025)
Payments for termination of interest rate swaps	(49,225)	0
Contributions from (distributions to) affiliates	0	0
Net intercompany activity	0	0
Payment of tax withholding for unit-based compensation	(8,820)	(6,368)
Other, net	(14,402)	(8,169)
Net cash (used in) provided by financing activities	(162,319)	73,757
Effect of foreign exchange rate changes on cash	(945)	261
Net increase (decrease) in cash, cash equivalents and restricted cash	1,097	11,238
Cash, cash equivalents and restricted cash as of the beginning of the period	24,980	13,644
Cash, cash equivalents and restricted cash as of the end of the period	26,077	24,882
Eliminations [Member]
Cash flows from operating activities:
Net cash provided by operating activities	(484,635)	(284,816)
Cash flows from investing activities:
Capital expenditures	0	0
Change in accounts payable related to capital expenditures	0	0
Proceeds from sale or disposition of assets	0	0
Investment in subsidiaries		11,999
Net cash (used in) provided by investing activities	0	11,999
Cash flows from financing activities:
Debt borrowings	0	0
Proceeds from note offering, net of issuance costs		0
Debt repayments	0	0
Distributions to preferred unitholders	91,272	91,272
Distributions to common unitholders	163,277	193,544
Payments for termination of interest rate swaps	0
Contributions from (distributions to) affiliates	230,086	(11,999)
Net intercompany activity	0	0
Payment of tax withholding for unit-based compensation	0	0
Other, net	0	0
Net cash (used in) provided by financing activities	484,635	272,817
Effect of foreign exchange rate changes on cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	0	0
Cash, cash equivalents and restricted cash as of the beginning of the period	0	0
Cash, cash equivalents and restricted cash as of the end of the period	0	0
Parent Company Guarantor [Member] \| NuStar Energy \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	167,758	187,265
Cash flows from investing activities:
Capital expenditures	0	0
Change in accounts payable related to capital expenditures	0	0
Proceeds from sale or disposition of assets	0	0
Investment in subsidiaries		0
Net cash (used in) provided by investing activities	0	0
Cash flows from financing activities:
Debt borrowings	0	0
Proceeds from note offering, net of issuance costs		0
Debt repayments	0	0
Distributions to preferred unitholders	(60,846)	(60,846)
Distributions to common unitholders	(108,846)	(129,025)
Payments for termination of interest rate swaps	0
Contributions from (distributions to) affiliates	0	0
Net intercompany activity	12,059	9,641
Payment of tax withholding for unit-based compensation	(8,820)	(6,368)
Other, net	(1,217)	(1,436)
Net cash (used in) provided by financing activities	(167,670)	(188,034)
Effect of foreign exchange rate changes on cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	88	(769)
Cash, cash equivalents and restricted cash as of the beginning of the period	176	1,255
Cash, cash equivalents and restricted cash as of the end of the period	264	486
Subsidiary Issuer [Member] \| NuStar Logistics \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	73,526	77,144
Cash flows from investing activities:
Capital expenditures	(25,787)	(167,647)
Change in accounts payable related to capital expenditures	(12,492)	11,708
Proceeds from sale or disposition of assets	335	71
Investment in subsidiaries		(11,999)
Net cash (used in) provided by investing activities	(37,944)	(167,867)
Cash flows from financing activities:
Debt borrowings	827,435	570,500
Proceeds from note offering, net of issuance costs		491,665
Debt repayments	(734,015)	(785,000)
Distributions to preferred unitholders	(30,424)	(30,424)
Distributions to common unitholders	(54,423)	(64,512)
Payments for termination of interest rate swaps	(49,225)
Contributions from (distributions to) affiliates	0	0
Net intercompany activity	18,680	(75,900)
Payment of tax withholding for unit-based compensation	0	0
Other, net	(12,918)	(6,581)
Net cash (used in) provided by financing activities	(34,890)	99,748
Effect of foreign exchange rate changes on cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	692	9,025
Cash, cash equivalents and restricted cash as of the beginning of the period	8,812	51
Cash, cash equivalents and restricted cash as of the end of the period	9,504	9,076
Guarantor Subsidiaries [Member] \| NuPOP \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	297,417	60,539
Cash flows from investing activities:
Capital expenditures	(5,596)	(9,131)
Change in accounts payable related to capital expenditures	(1,325)	522
Proceeds from sale or disposition of assets	117	26
Investment in subsidiaries		0
Net cash (used in) provided by investing activities	(6,804)	(8,583)
Cash flows from financing activities:
Debt borrowings	0	0
Proceeds from note offering, net of issuance costs		0
Debt repayments	0	0
Distributions to preferred unitholders	(30,424)	(30,423)
Distributions to common unitholders	(54,423)	(64,512)
Payments for termination of interest rate swaps	0
Contributions from (distributions to) affiliates	0	0
Net intercompany activity	(205,545)	43,009
Payment of tax withholding for unit-based compensation	0	0
Other, net	(221)	(30)
Net cash (used in) provided by financing activities	(290,613)	(51,956)
Effect of foreign exchange rate changes on cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	0	0
Cash, cash equivalents and restricted cash as of the beginning of the period	0	0
Cash, cash equivalents and restricted cash as of the end of the period	0	0
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	216,375	200,762
Cash flows from investing activities:
Capital expenditures	(64,975)	(143,183)
Change in accounts payable related to capital expenditures	(1,692)	3,914
Proceeds from sale or disposition of assets	5,335	46
Investment in subsidiaries		0
Net cash (used in) provided by investing activities	(61,332)	(139,223)
Cash flows from financing activities:
Debt borrowings	14,600	23,800
Proceeds from note offering, net of issuance costs		0
Debt repayments	(28,200)	(22,800)
Distributions to preferred unitholders	(30,424)	(30,425)
Distributions to common unitholders	(54,431)	(64,520)
Payments for termination of interest rate swaps	0
Contributions from (distributions to) affiliates	(230,086)	11,999
Net intercompany activity	174,806	23,250
Payment of tax withholding for unit-based compensation	0	0
Other, net	(46)	(122)
Net cash (used in) provided by financing activities	(153,781)	(58,818)
Effect of foreign exchange rate changes on cash	(945)	261
Net increase (decrease) in cash, cash equivalents and restricted cash	317	2,982
Cash, cash equivalents and restricted cash as of the beginning of the period	15,992	12,338
Cash, cash equivalents and restricted cash as of the end of the period	$ 16,309	$ 15,320

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