Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue
Revenue	$ 889,492	$ 896,612	$ 2,292,185	$ 2,980,757
Revenue from derivatives and other sources	(508,901)	222,269	(109,578)	475,195
Total revenue	380,591	1,118,881	2,182,607	3,455,952
Natural gas sales
Disaggregation of Revenue
Revenue	436,304	524,448	1,214,801	1,735,086
Oil sales
Disaggregation of Revenue
Revenue	34,265	40,561	78,233	137,675
Gathering and compression
Disaggregation of Revenue
Revenue				3,972
Water handling and treatment
Disaggregation of Revenue
Revenue				507
Marketing
Disaggregation of Revenue
Revenue	91,497	46,645	201,855	200,911
Exploration and production | Natural gas sales
Disaggregation of Revenue
Revenue	436,304	524,448	1,214,801	1,735,086
Exploration and production | Natural gas liquids sales (ethane)
Disaggregation of Revenue
Revenue	32,444	26,488	85,884	92,378
Exploration and production | Natural gas liquids sales (C3+ NGLs)
Disaggregation of Revenue
Revenue	294,982	258,470	711,412	810,228
Exploration and production | Oil sales
Disaggregation of Revenue
Revenue	34,265	40,561	78,233	137,675
Marketing | Marketing
Disaggregation of Revenue
Revenue	$ 91,497	$ 46,645	$ 201,855	$ 200,911