Short-term Borrowings and Long-term Debt - Schedule of Maturities (Details) $ in Millions	Dec. 31, 2024 USD ($)
Houston Electric
Debt Instrument [Line Items]
2025	$ 500
2026	300
2027	300
2028	500
2029	0
CERC
Debt Instrument [Line Items]
2025	10
2026	60
2027	625
2028	1,230
2029	30
Centerpoint Energy
Debt Instrument [Line Items]
2025	564
2026	2,274
2027	1,320
2028	2,063
2029	935
Securitization Bonds
Debt Instrument [Line Items]
2025	13
2026	14
2027	14
2028	15
2029	$ 16

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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