v3.8.0.1

PARTNERS' EQUITY Narrative 2 (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Apr. 18, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Class of Stock [Line Items] |  |  |  |
Equity issuance costs |  |  | $ 500 |
General partner ownership interest |  | 2.00% | 2.00% | 2.00%
Common Limited Partner [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Issuance of units (units) | 14,375,000 | 14,375,000 | 595,050 |
Units issued, price per unit | $ 46.35 |  |  |
Weighted average price per unit issued |  |  | $ 47.39 |
Proceeds from common unit issuance including general partner contribution | $ 657,500 |  | $ 28,300 |
Net proceeds from issuance of units |  | $ 643,878 | $ 27,710 |
Unit-based compensation (units) |  | 185,455 | 135,100 |
General Partner [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Net proceeds from issuance of units | $ 13,600 | $ 13,597 | $ 575 |
General partner ownership interest |  | 2.00% |  |

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- Definition Total change in each class of partners' capital accounts during the year due to the sale of units. All partners include general, limited and preferred partners. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 + Details
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