v3.19.3.a.u2

PARTNERS' EQUITY Table 2 - Balance of and Changes in Common Units Outstanding (Details) - shares |  |  |  | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Nov. 26, 2019 | Jun. 29, 2018 | Apr. 18, 2017 | Sep. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Limited partners common units outstanding (in units) |  |  |  |  | 108,527,806 | 107,225,156 |  |
Common Limited Partner [Member] |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |
Limited partners common units outstanding (in units) |  |  |  |  | 108,527,806 | 107,225,156 | 93,176,683 | 78,616,228
Issuance of units (units) | 527,426 | 413,736 | 14,375,000 |  | 527,426 | 413,736 | 14,375,000 |
Unit-based compensation (units) |  |  |  |  | 775,224 | 225,144 | 185,455 |
Issuance of NuStar Energy common units as a result of the Merger, incremental units issued |  |  |  | 13,400,000 | 0 | 13,409,593 | 0 |

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