For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Revenue from Contracts with Customers Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 458,382	$ 294,459	$ 1,243,826	$ 912,596
Revenue, Remaining Performance Obligation, Amount	0		0
Permian
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	311,013	123,433	801,306	307,986
South Texas & Gulf Coast
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	147,369	135,818	385,284	480,630
Rocky Mountain
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 35,208	$ 57,236	$ 123,980
Sales Revenue, Net \| Geographic Concentration Risk
Segment Reporting Information [Line Items]
Relative percentage	100.00%	100.00%	100.00%	100.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Permian
Segment Reporting Information [Line Items]
Relative percentage	68.00%	42.00%	64.00%	34.00%
Sales Revenue, Net \| Geographic Concentration Risk \| South Texas & Gulf Coast
Segment Reporting Information [Line Items]
Relative percentage	32.00%	46.00%	31.00%	53.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Rocky Mountain
Segment Reporting Information [Line Items]
Relative percentage	0.00%	12.00%	5.00%	13.00%
Oil Revenue [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 287,522	$ 154,203	$ 814,732	$ 450,701
Oil Revenue [Member] \| Permian
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	270,086	107,248	703,516	267,301
Oil Revenue [Member] \| South Texas & Gulf Coast
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	17,436	13,726	56,365	65,662
Oil Revenue [Member] \| Rocky Mountain
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	33,229	54,851	117,738
Natural Gas Revenue [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	96,810	86,265	259,983	289,156
Natural Gas Revenue [Member] \| Permian
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	40,364	16,034	96,974	40,280
Natural Gas Revenue [Member] \| South Texas & Gulf Coast
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	56,446	69,069	161,414	245,030
Natural Gas Revenue [Member] \| Rocky Mountain
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	0	1,162	1,595	3,846
Oil and Condensate Revenue [Member]
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	74,050	53,991	169,111	172,739
Oil and Condensate Revenue [Member] \| Permian
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	563	151	816	405
Oil and Condensate Revenue [Member] \| South Texas & Gulf Coast
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	73,487	53,023	167,505	169,938
Oil and Condensate Revenue [Member] \| Rocky Mountain
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 817	$ 790	$ 2,396