v3.19.3.a.u2

PARTNERS' EQUITY Narrative 2 (Details) - USD ($) $ / shares in Units, $ in Thousands				6 Months Ended	9 Months Ended	12 Months Ended
	Nov. 26, 2019	Jun. 29, 2018	Apr. 18, 2017	Jun. 30, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Proceeds from issuance of common units, net of issuance costs	$ 15,000					$ 15,000	$ 10,000	$ 643,878
Contributions from general partner						$ 0	$ 204	$ 13,737
General partner ownership interest				2.00%				2.00%
Common Limited Partner [Member]
Class of Stock [Line Items]
Issuance of units (units)	527,426	413,736	14,375,000			527,426	413,736	14,375,000
Units issued, price per unit	$ 28.44	$ 24.17	$ 46.35
Issuance of NuStar Energy common units as a result of the Merger, incremental units issued					13,400,000	0	13,409,593	0
Proceeds from common unit issuance including general partner contribution		$ 10,200	$ 657,500
Unit-based compensation (units)						775,224	225,144	185,455
General Partner [Member]
Class of Stock [Line Items]
Contributions from general partner			$ 13,600		$ 200
General partner ownership interest				2.00%

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Conversion of Stock, Incremental Shares Issued

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Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.

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