Represents the margin over out-of-pocket costs for water handling and treatment related to revenue recognition.

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The post-closure period to maintain and monitor landfill after it is certified closed.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Amount of interest capitalized during the period.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Property and equipment:
Total property and equipment	$ 3,208,496		$ 3,208,496		$ 2,974,922
Less accumulated depreciation	(438,185)		(438,185)		(369,320)
Property and equipment, net	2,770,311		2,770,311		2,605,602
Interest cost capitalized	1,000	$ 3,000	$ 4,000	$ 6,000
Asset Retirement Obligations
Post-closure period for landfill to maintain and monitor			30 years
Impairment of Long-Lived Assets
Impairment of property and equipment	$ 4,614		$ 4,614
Stock-Based Compensation
Margin over out-of-pocket costs related to water handling and treatment for revenue recognition (as a percent)			3.00%
Midstream LTIP
Stock-Based Compensation
Number of stock-based compensation awards authorized	10,000,000		10,000,000
Land
Property and equipment:
Total property and equipment	$ 17,060		$ 17,060		15,382
Fresh water surface pipelines and equipment
Property and equipment:
Estimated useful lives			5 years
Total property and equipment	60,866		$ 60,866		46,139
Above ground storage tanks
Property and equipment:
Estimated useful lives			10 years
Total property and equipment	4,824		$ 4,824		4,301
Fresh water permanent buried pipelines and equipment
Property and equipment:
Estimated useful lives			20 years
Total property and equipment	505,900		$ 505,900		472,810
Gathering systems and facilities
Property and equipment:
Estimated useful lives			20 years
Total property and equipment	1,949,928		$ 1,949,928		1,781,386
Wastewater treatment facility
Property and equipment:
Estimated useful lives			30 years
Total property and equipment	302,902		$ 302,902
Landfill
Property and equipment:
Total property and equipment	52,560		$ 52,560
Heavy trucks and equipment
Property and equipment:
Estimated useful lives			5 years
Total property and equipment	4,831		$ 4,831
Construction-in-progress
Property and equipment:
Total property and equipment	$ 309,625		$ 309,625		654,904
Construction-in-progress - wastewater treatment facility
Property and equipment:
Total property and equipment					$ 355,000