Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended	42 Months Ended	57 Months Ended	180 Months Ended
	Dec. 31, 2020	Jul. 01, 2022	Dec. 31, 2022	Dec. 31, 2032
Commitments and Contingencies Disclosure [Abstract]
Current annual salaries of officers and key employees	$ 12
Loss Contingencies [Line Items]
Total lease payments	223
South Texas Divestiture
Loss Contingencies [Line Items]
Deficiency Fee Liability	(333)
Guarantor Obligations, Reimbursement	75
Guarantor Obligations, Liquidation Proceeds, Monetary Amount	100
Divestitures Obligations, Raton Transportation [Member]
Loss Contingencies [Line Items]
Guarantor Obligations, Liquidation Proceeds, Monetary Amount	50
Deficiency Fees Paid and Reimbursed	11
West Eagle Ford Shale
Loss Contingencies [Line Items]
Guarantor Obligations, Liquidation Proceeds, Monetary Amount	$ 19
Forecast [Member] | South Texas Divestiture
Loss Contingencies [Line Items]
Loss Contingency, Obligation, Percentage		10000.00%
Loss Contingency, Buyer Recovery, Percentage		18.00%
Maximum | South Texas Divestiture
Loss Contingencies [Line Items]
Loss Contingency, Obligation, Percentage	10000.00%
Deficiency Fee Liability	$ 388
Maximum | Divestitures Obligations, Raton Transportation [Member]
Loss Contingencies [Line Items]
Deficiency Fee Liability	77
Maximum | West Eagle Ford Shale
Loss Contingencies [Line Items]
Deficiency Fee Liability	24
Maximum | Forecast [Member] | South Texas Divestiture
Loss Contingencies [Line Items]
Loss Contingency, Obligation, Percentage		10000.00%
Loss Contingency, Buyer Recovery, Percentage		18.00%
Maximum | Forecast [Member] | Divestitures Obligations, Raton Transportation [Member]
Loss Contingencies [Line Items]
Loss Contingency, Obligation, Percentage				10000.00%
Maximum | Forecast [Member] | West Eagle Ford Shale
Loss Contingencies [Line Items]
Loss Contingency, Obligation, Percentage			10000.00%
Divestitures Obligations, South Texas [Member] | Other Current Liabilities [Member] | South Texas Divestiture
Loss Contingencies [Line Items]
Monetary sanctions	$ (144)