v3.10.0.1

Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information
Revenue									$ 1,027,939	$ 772,497	$ 586,352
Total operating expenses	$ 26,597	$ 140,159	$ 136,145	$ 118,051	$ 143,089	$ 110,458	$ 101,199	$ 93,073	420,952	447,819	332,100
Operating income	255,154	126,046	114,830	111,540	67,243	83,171	92,567	81,697	607,570	324,678	258,111
Net income	248,609	119,764	109,466	108,105	64,155	80,893	87,175	75,092
Less: general partner's interest in net income	(43,492)	(37,816)	(33,145)	(28,453)	(23,772)	(19,067)	(15,328)	(11,553)	(142,906)	(69,720)	(16,944)
Limited partners' interest in net income	$ 205,117	$ 81,948	$ 76,321	$ 79,652	$ 40,383	$ 61,826	$ 71,847	$ 63,539	$ 443,038	$ 237,595	$ 219,759
Net income per limited partner unit - basic and diluted					$ 0.22	$ 0.33	$ 0.39	$ 0.35
Net income per limited partner unit - basic	$ 1.10	$ 0.44	$ 0.41	$ 0.43					$ 2.37	$ 1.28	$ 1.24
Net income per limited partner unit - diluted	$ 1.09	$ 0.44	$ 0.41	$ 0.43					$ 2.36	$ 1.28	$ 1.24
Impairment of property and equipment					$ 23,000				$ 5,771	$ 23,431
Reduction of fair value of the liability for contingent acquisition consideration	$ 106,000								$ 106,000

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

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Aggregate amount of net income allocated to limited partners.

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Per unit of ownership amount after tax of income (loss) available to limited partnership (LP) unit-holder and units that would have been outstanding assuming the issuance of limited partner units for dilutive potential units outstanding.

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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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Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) unit-holder.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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