Income Taxes - EGTS (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Schedule of Effective Income Tax Rate Reconciliation [Line Items]
Federal statutory income tax rate	21.00%	21.00%	21.00%	21.00%
State income tax, net of federal income tax impacts	0.00%	(1.00%)	(2.00%)	0.00%
Other	0.00%	1.00%	0.00%	0.00%
Effective income tax rate	(24.00%)	5.00%	(21.00%)	(13.00%)
EGTS
Schedule of Effective Income Tax Rate Reconciliation [Line Items]
Federal statutory income tax rate	21.00%	21.00%	21.00%	21.00%
State income tax, net of federal income tax impacts	5.00%	7.00%	5.00%	6.00%
Allowance for funds used during construction-equity	(1.00%)	0.00%	0.00%	0.00%
Other	0.00%	0.00%	(1.00%)	0.00%
Effective income tax rate	25.00%	28.00%	25.00%	27.00%