Revenue from Contracts with Customers - EGTS - Remaining Performance Obligation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 24,099		$ 24,099
Operating revenue	6,229	$ 6,612	12,575	$ 12,642
Other | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	23	28	57	50
EGTS
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	4,096		4,096
Total Customer Revenue	234	233	511	463
Other revenue	2	1	3	(6)
Operating revenue	236	234	514	457
EGTS | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	219	214	479	426
EGTS | Nonregulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	15	19	32	37
EGTS | Gas transmission | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	151	145	342	310
EGTS | Gas storage | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	70	69	137	116
EGTS | Other | Regulated
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total Customer Revenue	(2)	$ 0	0	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 3,335		$ 3,335
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]: 2023-07-01 | EGTS
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 757		$ 757
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]: 2024-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 20,764		$ 20,764
Performance obligations expected to be satisfied, expected timing of satisfaction, period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-07-01 | EGTS
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 3,339		$ 3,339
Performance obligations expected to be satisfied, expected timing of satisfaction, period