v3.8.0.1

PARTNERS' EQUITY Table 6 - Cash Distributions Paid - General Partner and Common Limited Partners (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 29, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Distribution Made to Limited Partner [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Cash distributions applicable to common unitbolders and general partner (distribution earned) |  | $ 115,267 | $ 115,084 | $ 115,083 | $ 117,168 |  |  |  |  | $ 462,602 | $ 393,882 | $ 392,204
Common Limited Partner [Member] |  |  |  |  |  |  |  |  |  |  |  |
Distribution Made to Limited Partner [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Cash distributions per unit applicable to limited partners |  | $ 1.095 | $ 1.095 | $ 1.095 | $ 1.095 | $ 1.0950 | $ 1.0950 | $ 1.0950 | $ 1.0950 | $ 4.380 | $ 4.380 | $ 4.380
Distribution date of record (distribution earned) |  | Feb. 08, 2018 | Nov. 09, 2017 | Aug. 07, 2017 | May 08, 2017 |  |  |  |  |  |  |
Distribution payment date |  | Feb. 13, 2018 | Nov. 14, 2017 | Aug. 11, 2017 | May 12, 2017 |  |  |  |  |  |  |
Common Limited Partner [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |
Distribution Made to Limited Partner [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Distribution announcement date (distribution earned) | Jan. 29, 2018 |  |  |  |  |  |  |  |  |  |  |

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