| Cover Page Cover Page | Jun. 30, 2020 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Jun. 30, 2020 |
| Entity Registrant Name | CenterPoint Energy, Inc. |
| Entity File Number | 1-31447 |
| Entity Tax Identification Number | 74-0694415 |
| Entity Address, Address Line One | 1111 Louisiana |
| Entity Address, City or Town | Houston |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77002 |
| City Area Code | (713) |
| Local Phone Number | 207-1111 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001130310 |
| Entity Incorporation, State or Country Code | TX |
| Common Stock | New York Stock Exchange | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | CNP |
| Security Exchange Name | NYSE |
| Common Stock | Chicago Stock Exchange | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | CNP |
| Security Exchange Name | CHX |
| Depositary Shares | New York Stock Exchange | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Depositary Shares for 1/20 of 7.00% Series B Mandatory Convertible Preferred Stock, $0.01 par value |
| Trading Symbol | CNP/PB |
| Security Exchange Name | NYSE |
| CenterPoint Energy Houston Electric LLC [Member] | |
| Entity Information [Line Items] | |
| Entity Registrant Name | CenterPoint Energy Houston Electric, LLC |
| Entity File Number | 1-3187 |
| Entity Tax Identification Number | 22-3865106 |
| Entity Address, Address Line One | 1111 Louisiana |
| Entity Address, City or Town | Houston |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77002 |
| City Area Code | (713) |
| Local Phone Number | 207-1111 |
| Entity Central Index Key | 0000048732 |
| Entity Incorporation, State or Country Code | TX |
| CenterPoint Energy Houston Electric LLC [Member] | 9.15% First Mortgage Bonds due 2021 [Member] | New York Stock Exchange | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | 9.15% First Mortgage Bonds due 2021 |
| Trading Symbol | n/a |
| Security Exchange Name | NYSE |
| CenterPoint Energy Houston Electric LLC [Member] | 6.95% General Mortgage Bonds due 2033 [Member] | New York Stock Exchange | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | 6.95% General Mortgage Bonds due 2033 |
| Trading Symbol | n/a |
| Security Exchange Name | NYSE |
| CenterPoint Energy Resources Corp. [Member] | |
| Entity Information [Line Items] | |
| Entity Registrant Name | CenterPoint Energy Resources Corp. |
| Entity File Number | 1-13265 |
| Entity Tax Identification Number | 76-0511406 |
| Entity Address, Address Line One | 1111 Louisiana |
| Entity Address, City or Town | Houston |
| City Area Code | (713) |
| Entity Central Index Key | 0001042773 |
| Entity Incorporation, State or Country Code | DE |
| CenterPoint Energy Resources Corp. [Member] | 6.625% Senior Notes due 2037 [Member] | New York Stock Exchange | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | 6.625% Senior Notes due 2037 |
| Trading Symbol | n/a |
| Security Exchange Name | NYSE |
