Net Income Per Limited Partner Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net income per limited partner unit
Net income	$ 80,893	$ 70,524	$ 243,160	$ 163,352
Net income attributable to incentive distribution rights	(19,067)	(4,807)	(45,948)	(9,387)
Limited partners' interest in net income	$ 61,826	$ 65,717	$ 197,212	$ 153,965
Net income per limited partner unit - basic and diluted	$ 0.33	$ 0.37	$ 1.06	$ 0.87
Weighted average limited partner units outstanding - basic	186,581,000	176,395,000	185,240,000	176,243,000
Weighted average limited partner units outstanding - diluted	187,145,000	176,766,000	185,728,000	176,306,000
Phantom share units
Net income per limited partner unit
Weighted average limited partner units outstanding - diluted	563,817		488,515
Common units
Net income per limited partner unit
Weighted average limited partner units outstanding - diluted	187,144,983		185,728,119

Aggregate amount of net income allocated to general partners subsequent to IPO.

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Aggregate amount of net income allocated to limited partners subsequent to IPO.

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Amount, before tax, of income (loss) attributable to parent. Includes, but is not limited to, income (loss) from continuing operations, discontinued operations and equity method investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.20)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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The amount of net income or loss for the period per each limited partnership and general partnership unit in instances when basic and diluted earnings per unit are the same amount and aggregated on the face of the financial statements. Basic earnings per unit is the amount of net income or loss for the period per unit outstanding during the reporting period. Diluted earnings per unit includes the amount of net income or loss for the period available to each limited and general partnership unit outstanding during the reporting period and to each unit that would have been outstanding assuming the issuance of units for all dilutive potential units outstanding during the reporting period.

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Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that limited partnership units have been outstanding to the total time in that period.

+ References

Reference 1: 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

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