v3.8.0.1

Partnership Equity and Distributions (Details) $ / shares in Units, $ in Thousands |  |  |  |  |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 16, 2017 USD ($) $ / shares | May 10, 2017 USD ($) $ / shares | Apr. 30, 2017 USD ($) | Feb. 09, 2017 shares | Feb. 08, 2017 USD ($) $ / shares | Nov. 24, 2016 USD ($) $ / shares | Nov. 08, 2016 USD ($) | Aug. 24, 2016 USD ($) $ / shares | May 25, 2016 USD ($) $ / shares | Feb. 29, 2016 USD ($) $ / shares | Sep. 30, 2017 $ / shares | Sep. 30, 2017 $ / shares $ / item | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual cash distribution (per unit) |  |  |  |  |  |  |  |  |  |  |  | 0.68 |  |
Minimum cash distributions to trigger unitholder and general partner distributions | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 0.1955 |  |
Cash distribution declared | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 0.34 |  |  |
Subordinated units | shares |  |  |  | 75,940,957 |  |  |  |  |  |  |  |  |  |
Common units conversion ratio |  |  |  | 1 |  |  |  |  |  |  |  |  |  |
Distributions | $ | $ 75,023 | $ 67,306 | $ 75 |  | $ 57,633 | $ 51,845 | $ 849 | $ 46,775 | $ 43,252 | $ 39,725 |  |  | $ 200,037 | $ 182,446
Distributions per limited partner unit (in dollars per share) | $ / shares | $ 0.3200 | $ 0.3000 |  |  | $ 0.2800 | $ 0.2650 |  | $ 0.2500 | $ 0.2350 | $ 0.2200 |  |  |  |
General Partner |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions | $ | $ 15,328 | $ 11,553 |  |  | $ 7,543 | $ 4,820 |  | $ 2,731 | $ 1,850 | $ 969 |  |  | 34,424 | 10,370
Common units |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions | $ | $ 59,695 | $ 55,753 | $ 75 |  | $ 50,090 | 26,901 | $ 849 | 25,059 | 23,556 | 22,048 |  |  | $ 165,613 | 98,413
Limited Partner (Subordinated units) | Limited Partner (Common units) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions | $ |  |  |  |  |  | $ 20,124 |  | $ 18,985 | $ 17,846 | $ 16,708 |  |  |  | $ 73,663
Above $0.1955 up to $0.2125 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unitholders marginal percentage interest in distribution |  |  |  |  |  |  |  |  |  |  |  | 85.00% |  |
General Partners marginal percentage interest in distribution |  |  |  |  |  |  |  |  |  |  |  | 15.00% |  |
Above $0.2125 up to $0.2550 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unitholders marginal percentage interest in distribution |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |
General Partners marginal percentage interest in distribution |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |
Above $0.2550 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unitholders marginal percentage interest in distribution |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |
General Partners marginal percentage interest in distribution |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |
Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum quarterly cash distribution (per unit) |  |  |  |  |  |  |  |  |  |  |  | 0.17 |  |
Minimum | Above $0.1955 up to $0.2125 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro rata cash distribution to the holders of common and subordinate units |  |  |  |  |  |  |  |  |  |  |  | 0.1955 |  |
Minimum | Above $0.2125 up to $0.2550 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro rata cash distribution to the holders of common and subordinate units |  |  |  |  |  |  |  |  |  |  |  | 0.2125 |  |
Minimum | Above $0.2550 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro rata cash distribution to the holders of common and subordinate units |  |  |  |  |  |  |  |  |  |  |  | 0.2550 |  |
Maximum | Above $0.1955 up to $0.2125 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro rata cash distribution to the holders of common and subordinate units |  |  |  |  |  |  |  |  |  |  |  | 0.2125 |  |
Maximum | Above $0.2125 up to $0.2550 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partnership equity and distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro rata cash distribution to the holders of common and subordinate units |  |  |  |  |  |  |  |  |  |  |  | 0.2550 |  |

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