v3.25.3
Related Party Transactions (Houston Electric and CERC) - Schedule of Amounts Charged For Services (Details) - Operation and maintenance expense - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Houston Electric        
Related Party Transaction [Line Items]        
Affiliate service charges (billings), net $ (2) $ (1) $ (3) $ (4)
CERC        
Related Party Transaction [Line Items]        
Affiliate service charges (billings), net 2 1 3 4
CenterPoint Energy | Houston Electric        
Related Party Transaction [Line Items]        
Corporate service charges 52 45 142 124
CenterPoint Energy | CERC        
Related Party Transaction [Line Items]        
Corporate service charges $ 58 $ 50 $ 164 $ 156