Acquisitions and Divestitures - Narrative (Details) MBoe in Thousands				12 Months Ended
	Dec. 06, 2018 USD ($) a MBoe wells numberOfDrillingLocations	Apr. 03, 2018 USD ($)	Apr. 03, 2017 USD ($) a MBoe wells	Dec. 31, 2018 USD ($) MBoe rig		Dec. 31, 2017 USD ($) MBoe rig	Dec. 31, 2016 USD ($) MBoe rig	Dec. 31, 2015 MBoe
Acquisitions and Divestitures [Line Items]
Proved Developed Reserves (Volume) | MBoe				111,576		112,961	99,079	115,296
Impairments				$ 147,884,000		$ 0	$ 161,563,000
EOG Acquisition
Acquisitions and Divestitures [Line Items]
Total consideration given			$ 54,332,000
Business Acquisition, Effective Date of Acquisition			Jan. 01, 2017
Proved Developed Reserves (Volume) | MBoe			3,200
Natural Gas Gathering System			1
Excalibur Acquisition
Acquisitions and Divestitures [Line Items]
Total consideration given	$ 29,633,000
Business Acquisition, Effective Date of Acquisition	Nov. 01, 2018
Proved Developed Reserves (Volume) | MBoe	2,600
Horizontal drilling locations | numberOfDrillingLocations	30
Acquired land with existing production capacity, percent	82.00%
Hoxbar | EOG Acquisition
Acquisitions and Divestitures [Line Items]
Area of Real Estate Property | a			8,300
Proved developed producing wells | wells			47
Acquired land with existing production capacity, percent			71.00%
Penn Sands | Excalibur Acquisition
Acquisitions and Divestitures [Line Items]
Area of Real Estate Property | a	8,667
Wells acquired | wells	44
Oil and Natural Gas
Acquisitions and Divestitures [Line Items]
Other acquisitions				600,000		4,700,000	600,000
Proceeds from divestiture of assets				22,500,000		18,600,000	67,200,000
Impairments				$ 0	[1]	$ 0	$ 161,600,000
Drilling Equipment
Acquisitions and Divestitures [Line Items]
Number of rigs sold | rig						0	1
Number of drilling rigs removed from service | rig				41
Net book value of drilling rigs sold							$ 1,700,000
Gain (loss) on sale of drilling rigs							1,600,000
Impairments				$ 147,900,000		$ 0	$ 0
Impairment of contract drilling equipment, net of tax				$ 111,700,000
Mechanical drilling rigs | Drilling Equipment
Acquisitions and Divestitures [Line Items]
Number of drilling rigs removed from service | rig				29
SCR diesel-electric drilling rigs | Drilling Equipment
Acquisitions and Divestitures [Line Items]
Number of drilling rigs removed from service | rig				12
Ownership interest in Superior Pipeline Company, L.L.C.
Acquisitions and Divestitures [Line Items]
Ownership interest sold		50.00%
Proceeds from sale of non-controlling interest		$ 300,000,000.0

[1] Impairment for contract drilling equipment includes a $147.9 million pre-tax write-down for 41 drilling rigs and other drilling equipment.