v3.26.3
Income Taxes (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Income Tax Disclosure [Abstract]        
Income before income taxes (domestic) $ 225 $ 180 $ 388 $ 303
Tax Jurisdiction of Domicile [Extensible Enumeration]     UNITED STATES  
Federal statutory rate impact     $ 82 64
PTCs (a) [1]     (104) (83)
Other     (1) (1)
AFUDC equity [2]     (14) (5)
Plant related excess deferred taxes [2]     (8) (10)
Adjustment to tax reform implementation [2]     0 10
Other [2]     2 2
State income taxes, net of federal tax effect (c) [3]     7 9
Other     1 (3)
Income tax expense (benefit) $ 9 $ 20 $ (35) $ (17)
Federal statutory rate     21.00% 21.00%
PTCs (a) [1]     (26.80%) (27.50%)
Other     (0.30%) (0.30%)
AFUDC equity [2]     (3.50%) (1.70%)
Plant related excess deferred taxes [2]     (1.90%) (3.50%)
Adjustment to tax reform implementation [2]     0.00% 3.20%
Other [2]     0.70% 0.80%
State income taxes, net of federal tax effect (c) [3]     1.80% 2.80%
Other     0.00% (0.40%)
Effective income tax rate     (9.00%) (5.60%)
[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 changes 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 New Mexico state taxes.