Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Schedule of Gain (Loss) On Equity Securities (CenterPoint Energy) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Debt and Equity Securities, FV-NI [Line Items] | ||||
| Total gains (losses) on equity securities, net | $ 43 | $ 19 | $ 122 | $ (64) |
| AT&T Common | ||||
| Debt and Equity Securities, FV-NI [Line Items] | ||||
| Total gains (losses) on equity securities, net | 7 | 15 | 63 | 24 |
| Charter Common | ||||
| Debt and Equity Securities, FV-NI [Line Items] | ||||
| Total gains (losses) on equity securities, net | 34 | 7 | 57 | (78) |
| WBD Common | ||||
| Debt and Equity Securities, FV-NI [Line Items] | ||||
| Total gains (losses) on equity securities, net | $ 2 | $ (3) | $ 2 | $ (10) |