NET INCOME PER UNIT Table (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Schedule Of Net Income Per Unit [Line Items]
Net income (loss) attributable to NuStar Energy L.P.	$ (246,737)	$ 92,599	$ (220,386)	$ 121,101
Less general partner distribution (including IDR)	11,598	10,590	23,196	20,750
Less limited partner distribution	77,478	70,749	154,956	140,205
Distributions less than (greater than) earnings	(335,813)	11,260	(398,538)	(39,854)
General partner earnings:
Distributions	11,598	10,590	23,196	20,750
Allocation of distributions less than (greater than) earnings (2%)	(6,717)	225	(7,972)	(798)
Total	4,881	10,815	15,224	19,952
Limited partner earnings:
Limited partners' distribution	77,478	70,749	154,956	140,205
Allocation of distributions less than (greater than) earnings (98%)	(329,096)	11,035	(390,566)	(39,056)
Total	$ (251,618)	$ 81,784	$ (235,610)	$ 101,149
Weighted-average limited partner units outstanding	70,756,078	64,610,549	70,756,078	64,610,549
Net income (loss) per unit applicable to limited partners	$ (3.56)	$ 1.27	$ (3.33)	$ 1.57

Net income less general and limited partner distributions.

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