Effective Tax Rate Reconciliation (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest		$ 355	$ 337	$ 339
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount		75	71	71
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	[1]	(115)	(115)	(114)
Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount		(1)	(1)	(2)
Effective Income Tax Rate Reconciliation, Plant Related Excess Deferred Taxes, Amount	[2]	(14)	(14)	(12)
Effective Income Tax Rate Reconciliation, AFUDC Equity, Amount	[2]	(7)	(4)	(1)
Effective Income Tax Rate Reconciliation, Adjustments to tax reform implementation, amount	[2]	10
Effective Income Tax Rate Reconciliation, Other Regulatory Adjustments, Amount	[2]	3	1	2
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	[3]	11	5	9
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount		(2)	0	2
Total income tax benefit		$ (40)	$ (57)	$ (45)
Federal statutory rate		21.00%	21.00%	21.00%
Effective Income Tax Rate Reconciliation, Tax Credit, Percent	[1]	(32.60%)	(34.30%)	(33.50%)
Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent		(0.30%)	(0.40%)	(0.50%)
Effective Income Tax Rate Reconciliation, Plant Related Excess Deferred Taxes, Percent	[2]	(3.90%)	(4.20%)	(3.40%)
Effective Income Tax Rate Reconciliation, AFUDC Equity, Percent	[2]	(1.80%)	(1.00%)	(0.40%)
Effective Income Tax Rate Reconciliation, Adjustments to tax reform implementation, percent	[2]	2.70%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Other Regulatory Adjustments, Percent	[2]	0.80%	0.40%	0.70%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	[3]	3.20%	1.50%	2.60%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent		(0.40%)	0.10%	0.20%
Effective Income Tax Rate Reconciliation, Percent		(11.30%)	(16.90%)	(13.30%)

[1] Wind PTCs (net of transfer discounts) are generally credited to customers (reduction to revenue) and do not materially impact earnings.

[2] Regulatory adjustments primarily relate to the credit of plant related excess deferred taxes to customers for tax rate increases as well as the capitalization of AFUDC equity for book purposes only. Income tax benefits associated with the credit of excess deferred taxes are offset by corresponding revenue reductions.

[3] State and local income taxes are primarily made up of the following jurisdictions: Texas