v3.26.1
Income Taxes - MEC - Reconciliation of Effective Income Tax Rate (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Amount    
U.S. federal statutory income tax rate $ 184 $ 200
State and local income taxes, net of federal income tax effect 18 14
Energy-related tax credits (564) (560)
Other adjustments:    
Effects of ratemaking (19) (25)
Total $ (430) $ (399)
Percent    
U.S. federal statutory income tax rate 21.00% 21.00%
State and local income taxes, net of federal income tax 2.10% 1.50%
Energy-related tax credits (64.20%) (58.80%)
Other adjustments:    
Effects of ratemaking (2.30%) (2.60%)
Effective income tax rate (49.00%) (41.80%)
MEC    
Amount    
U.S. federal statutory income tax rate $ 7 $ (1)
State and local income taxes, net of federal income tax effect (1) 0
Energy-related tax credits (222) (236)
Other adjustments:    
Effects of ratemaking 0 1
Total $ (216) $ (236)
Percent    
U.S. federal statutory income tax rate 21.00% 21.00%
State and local income taxes, net of federal income tax (2.50%) 0.00%
Energy-related tax credits (693.80%) 5900.00%
Other adjustments:    
Effects of ratemaking 0.00% (21.00%)
Effective income tax rate (675.30%) 5900.00%