Revenue from Contracts with Customers - EGTS - Remaining Performance Obligation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 23,414		$ 23,414
Operating revenue	7,170	$ 7,500	19,745	$ 20,142
Other | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	39	24	96	74
EGTS
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	3,935		3,935
Total Customer Revenue	233	244	744	707
Other revenue	0	(4)	3	(10)
Operating revenue	233	240	747	697
EGTS | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	219	225	698	651
EGTS | Nonregulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	14	19	46	56
EGTS | Gas transmission | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	144	151	486	461
EGTS | Gas storage | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	69	74	206	190
EGTS | Other | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	6	$ 0	6	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 3,136		$ 3,136
Performance obligations expected to be satisfied, expected timing of satisfaction, period	12 months		12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01 | EGTS
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 764		$ 764
Performance obligations expected to be satisfied, expected timing of satisfaction, period	12 months		12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 20,278		$ 20,278
Performance obligations expected to be satisfied, expected timing of satisfaction, period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 | EGTS
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 3,171		$ 3,171
Performance obligations expected to be satisfied, expected timing of satisfaction, period