CONDENSED CONSOLIDATING FINANCIAL STATEMENTS Table 3 - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net cash provided by operating activities	$ 151,428	$ 103,568
Cash flows from investing activities:
Capital expenditures	(56,283)	(159,429)
Change in accounts payable related to capital expenditures	(15,706)	19,401
Proceeds from sale or disposition of assets	565	79
Net cash (used in) provided by investing activities	(71,424)	(139,949)
Cash flows from financing activities:
Debt borrowings	187,200	311,500
Debt repayments	(152,115)	(158,100)
Distributions to preferred unitholders	(30,423)	(30,423)
Distributions to common unitholders	(65,169)	(64,367)
Contributions from (distributions to) affiliates	0
Net intercompany activity	0	0
Payment of tax withholding for unit-based compensation	(8,820)	(6,366)
Other, net	(7,762)	(5,127)
Net cash (used in) provided by financing activities	(77,089)	47,117
Effect of foreign exchange rate changes on cash	(1,403)	154
Net increase (decrease) in cash, cash equivalents and restricted cash	1,512	10,890
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	26,492	24,534
Cash and cash equivalents as of the end of the period	17,694
Eliminations [Member]
Cash flows from operating activities:
Net cash provided by operating activities	(373,479)	(142,190)
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
Net cash (used in) provided by investing activities	0	0
Cash flows from financing activities:
Debt borrowings	0	0
Debt repayments	0	0
Distributions to preferred unitholders	45,636	45,635
Distributions to common unitholders	97,757	96,555
Contributions from (distributions to) affiliates	230,086
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	373,479	142,190
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
Cash and cash equivalents as of the end of the period	0
Parent Company Guarantor [Member] \| NuStar Energy \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	94,676	93,209
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
Net cash (used in) provided by investing activities	0	0
Cash flows from financing activities:
Debt borrowings	0	0
Debt repayments	0	0
Distributions to preferred unitholders	(30,423)	(30,423)
Distributions to common unitholders	(65,169)	(64,367)
Contributions from (distributions to) affiliates	0
Net intercompany activity	10,469	8,948
Payment of tax withholding for unit-based compensation	(8,820)	(6,366)
Other, net	(658)	(893)
Net cash (used in) provided by financing activities	(94,601)	(93,101)
Effect of foreign exchange rate changes on cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	75	108
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	251	1,363
Cash and cash equivalents as of the end of the period	251
Subsidiary Issuer [Member] \| NuStar Logistics \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	64,365	26,732
Cash flows from investing activities:
Capital expenditures	(14,674)	(87,696)
Change in accounts payable related to capital expenditures	(12,807)	14,894
Proceeds from sale or disposition of assets	299	46
Net cash (used in) provided by investing activities	(27,182)	(72,756)
Cash flows from financing activities:
Debt borrowings	178,000	306,500
Debt repayments	(148,515)	(143,500)
Distributions to preferred unitholders	(15,212)	(15,212)
Distributions to common unitholders	(32,584)	(32,183)
Contributions from (distributions to) affiliates	0
Net intercompany activity	(10,246)	(55,453)
Payment of tax withholding for unit-based compensation	0	0
Other, net	(6,974)	(4,227)
Net cash (used in) provided by financing activities	(35,531)	55,925
Effect of foreign exchange rate changes on cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	1,652	9,901
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	10,464	9,952
Cash and cash equivalents as of the end of the period	1,666
Guarantor Subsidiaries [Member] \| NuPOP \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	265,236	11,953
Cash flows from investing activities:
Capital expenditures	(1,506)	(2,253)
Change in accounts payable related to capital expenditures	(3,390)	15,532
Proceeds from sale or disposition of assets	48	1
Net cash (used in) provided by investing activities	(4,848)	13,280
Cash flows from financing activities:
Debt borrowings	0	0
Debt repayments	0	0
Distributions to preferred unitholders	(15,212)	(15,212)
Distributions to common unitholders	(32,584)	(32,183)
Contributions from (distributions to) affiliates	0
Net intercompany activity	(212,484)	22,164
Payment of tax withholding for unit-based compensation	0	0
Other, net	(108)	(2)
Net cash (used in) provided by financing activities	(260,388)	(25,233)
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
Cash and cash equivalents as of the end of the period	0
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by operating activities	100,630	113,864
Cash flows from investing activities:
Capital expenditures	(40,103)	(69,480)
Change in accounts payable related to capital expenditures	491	(11,025)
Proceeds from sale or disposition of assets	218	32
Net cash (used in) provided by investing activities	(39,394)	(80,473)
Cash flows from financing activities:
Debt borrowings	9,200	5,000
Debt repayments	(3,600)	(14,600)
Distributions to preferred unitholders	(15,212)	(15,211)
Distributions to common unitholders	(32,589)	(32,189)
Contributions from (distributions to) affiliates	(230,086)
Net intercompany activity	212,261	24,341
Payment of tax withholding for unit-based compensation	0	0
Other, net	(22)	(5)
Net cash (used in) provided by financing activities	(60,048)	(32,664)
Effect of foreign exchange rate changes on cash	(1,403)	154
Net increase (decrease) in cash, cash equivalents and restricted cash	(215)	881
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	15,777	$ 13,219
Cash and cash equivalents as of the end of the period	$ 15,777

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