Revenue Recognition (Disaggregation of Revenue on Geographic Basis) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 6,667	$ 2,308	$ 3,038
Exploration and Production
Disaggregation of Revenue [Line Items]
Total operating revenues	4,701	1,391	1,740
Exploration and Production | Operating Segments
Disaggregation of Revenue [Line Items]
Total operating revenues	4,640	1,348	1,703
Appalachia | Exploration and Production | Operating Segments
Disaggregation of Revenue [Line Items]
Total operating revenues	3,955	1,348	1,700
Haynesville | Exploration and Production | Operating Segments
Disaggregation of Revenue [Line Items]
Total operating revenues	682	0	0
Other | Exploration and Production | Operating Segments
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 3	$ 0	$ 3