v3.26.1
Income Taxes - SPPC - Reconciliation of Effective Income Tax Rate (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Amount        
U.S. federal statutory income tax rate $ 163 $ 115 $ 347 $ 315
Energy-related tax credits (415) (390) (979) (950)
Effects of ratemaking (30) (20) (49) (45)
Total $ (333) $ (357) $ (763) $ (756)
Percent        
U.S. federal statutory income tax rate 21.00% 21.00% 21.00% 21.00%
Energy-related tax credits (53.50%) (71.50%) (59.20%) (63.40%)
Effects of ratemaking (3.70%) (3.70%) (2.90%) (3.00%)
Effective income tax rate (42.90%) (65.60%) (46.10%) (50.50%)
SPPC        
Amount        
U.S. federal statutory income tax rate $ 7 $ 6 $ 13 $ 12
Energy-related tax credits (2) 0 (2) 0
Effects of ratemaking (8) (3) (13) (6)
Total $ (3) $ 3 $ (2) $ 6
Percent        
U.S. federal statutory income tax rate 21.00% 21.00% 21.00% 21.00%
Energy-related tax credits (7.00%) 0.00% (3.80%) 0.00%
Effects of ratemaking (22.50%) (9.90%) (20.80%) (9.60%)
Effective income tax rate (8.50%) 11.10% (3.60%) 11.40%