Subsequent Events (CenterPoint Energy) (Details) - $ / shares		3 Months Ended		6 Months Ended
	Jul. 21, 2022	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Common Stock
Subsequent Event [Line Items]
Common stock, dividends declared per share (in dollars per share)		$ 0.170	$ 0.160	$ 0.170	$ 0.160
Series A Preferred Stock
Subsequent Event [Line Items]
Preferred stock, dividends declared (in dollars per share)		$ 0	$ 0	$ 0	$ 0
Subsequent Event
Subsequent Event [Line Items]
Common stock, dividends declared per share (in dollars per share)	$ 0.1800
Subsequent Event | Series A Preferred Stock
Subsequent Event [Line Items]
Preferred stock, dividends declared (in dollars per share)	$ 30.6250