Revenue Recognition (Disaggregation of Revenue on Geographic Basis) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Total operating revenues	$ (1,443)	$ (4,541)	$ (4,830)	$ (11,622)
E&P
Disaggregation of Revenue [Line Items]
Total operating revenues	(890)	(3,243)	(3,123)	(8,251)
Operating Segments | E&P
Disaggregation of Revenue [Line Items]
Total operating revenues	(873)	(3,247)	(3,079)	(8,250)
Operating Segments | E&P | Appalachia
Disaggregation of Revenue [Line Items]
Total operating revenues	(500)	(1,874)	(1,891)	(4,971)
Operating Segments | E&P | Haynesville
Disaggregation of Revenue [Line Items]
Total operating revenues	$ (373)	$ (1,373)	$ (1,188)	$ (3,279)