Properties and Equipment (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($) Wells	Dec. 31, 2019 USD ($) Wells	Dec. 31, 2018 USD ($)
Property, Plant and Equipment [Line Items]
Document Period End Date	Jun. 30, 2020
Reclassification to Well, Facilities, and Equipment Based on Determination of Proved Reserves	$ (20,431)	$ (28,011)
Proved Natural Gas and Crude Oil Properties	7,369,104	6,241,780
Unproved Natural Gas and Crude Oil Properties	385,322	403,379
Total Natural Gas and Crude Oil Properties	7,754,426	6,645,159
Equipment and other	64,898	41,888
Land and Buildings	26,014	12,312
Construction in Progress	492,497	408,428
Properties and equipment, at cost	8,337,835	7,107,787
Accumulated DD&A	(3,337,769)	(3,012,585)
Property, Plant and Equipment, Net	5,000,066	4,095,202
Capitalized Exploratory Well Cost, Additions Pending Determination of Proved Reserves	11,556	31,901
Capitalized Exploratory Well Costs	$ 7,203	$ 16,078	$ 12,188
Wells to be completed | Wells	2	4