Revenue Recognition (Disaggregation of Revenue on Geographic Basis) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 1,269	$ 4,138	$ 3,387	$ 7,081
E&P
Disaggregation of Revenue [Line Items]
Total operating revenues	794	2,931	2,233	5,008
Operating Segments | E&P
Disaggregation of Revenue [Line Items]
Total operating revenues	777	2,929	2,206	5,003
Operating Segments | E&P | Appalachia
Disaggregation of Revenue [Line Items]
Total operating revenues	468	1,776	1,391	3,097
Operating Segments | E&P | Haynesville
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 309	$ 1,153	$ 815	$ 1,906