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Stock-Based Incentive Compensation Plans and Employee Benefit Plans - Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Savings Plan [Abstract]
Savings plan benefit expenses	$ 72	$ 67	$ 72
Postemployment Benefits [Abstract]
Deferred compensation plans	$ 3	(1)	1
Savings Plan
Savings Plan [Abstract]
Number of Common stock held by the savings plan (in shares)	7,136,941
Percentage of investment in common stocks (in hundredths)	6.00%
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 1,132	1,204	1,212
Obligation to return cash received as collateral from securities lending	(88)	(94)
Financial instruments	(3)	(4)
Defined benefits plan, fair value of plan assets, excluding investments measured at net asset value	690	744
Contributions in 2024	30	32
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	144
2026	144
2027	141
2028	138
2029	134
2030-2034	609
Pension Plan | Qualified pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions in 2024	23
Expected Minimum Contributions in 2025	105
Pension Plan | Non-qualified pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions in 2024	7
Expected Minimum Contributions in 2025	7
Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	103	112	109
Contributions in 2024	9	7
Expected Minimum Contributions in 2025	8
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	16
2026	18
2027	19
2028	20
2029	21
2030-2034	102
Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	220	229
Obligation to return cash received as collateral from securities lending	(88)	(94)
Financial instruments	0	0
Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	470	515
Obligation to return cash received as collateral from securities lending	0	0
Financial instruments	(3)	(4)
Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Obligation to return cash received as collateral from securities lending	0	0
Financial instruments	0	0
U.S. equity | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	28	30
U.S. equity | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	28	30
U.S. equity | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
U.S. equity | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Cash | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	36	21
Cash | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	36	21
Cash | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Cash | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Cash received as collateral from securities lending | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	88	94
Cash received as collateral from securities lending | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	88	94
Cash received as collateral from securities lending | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Cash received as collateral from securities lending | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
U.S. treasuries and government agencies | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	156	178
U.S. treasuries and government agencies | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	156	178
U.S. treasuries and government agencies | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
U.S. treasuries and government agencies | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Investment grade or above | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	428	469
Investment grade or above | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Investment grade or above | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	428	469
Investment grade or above | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Mortgage-backed securities | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	12	15
Mortgage-backed securities | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Mortgage-backed securities | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	12	15
Mortgage-backed securities | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Asset-backed securities | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	1	1
Asset-backed securities | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Asset-backed securities | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	1	1
Asset-backed securities | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Municipal bonds | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	19	25
Municipal bonds | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Municipal bonds | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	19	25
Municipal bonds | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
International government bonds | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	13	9
International government bonds | Level 1 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
International government bonds | Level 2 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	13	9
International government bonds | Level 3 | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Common Collective Trust Funds | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 442	$ 460
Common Collective Trust Funds | International equities | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	38.00%	40.00%
Common Collective Trust Funds | U.S. equity | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	61.00%	59.00%
Common Collective Trust Funds | Fixed income | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	1.00%	1.00%
Mutual funds | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 103	$ 113
Mutual funds | International equities | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	7.00%	8.00%
Mutual funds | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	19.00%	20.00%
Mutual funds | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	74.00%	72.00%
Mutual funds | Level 1 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 103	$ 113
Mutual funds | Level 2 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Mutual funds | Level 3 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Benefit Obligation
Postemployment Benefits [Abstract]
Deferred compensation plans	22	26
Split-dollar life insurance arrangements	$ 46	46
Minimum | U.S. equity | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	17.00%
Minimum | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	14.00%
Minimum | International equity | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	9.00%
Minimum | International equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	3.00%
Minimum | Real estate | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	2.00%
Minimum | Fixed income | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	54.00%
Minimum | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	69.00%
Minimum | Cash | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	0.00%
Minimum | Cash | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	0.00%
Maximum | U.S. equity | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	27.00%
Maximum | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	24.00%
Maximum | International equity | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	19.00%
Maximum | International equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	13.00%
Maximum | Real estate | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	8.00%
Maximum | Fixed income | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	64.00%
Maximum | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	79.00%
Maximum | Cash | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	2.00%
Maximum | Cash | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	2.00%
Common Stock | CenterPoint Energy | Savings Plan
Savings Plan [Abstract]
Maximum limit of account balance in company stock (as a percent)	25.00%
Houston Electric
Savings Plan [Abstract]
Savings plan benefit expenses	$ 27	23	23
Postemployment Benefits [Abstract]
Deferred compensation plans	0	0	0
Houston Electric | Pension Plan | Qualified pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions in 2024	0
Expected Minimum Contributions in 2025	0
Houston Electric | Pension Plan | Non-qualified pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions in 2024	0
Expected Minimum Contributions in 2025	0
Houston Electric | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	77	86	84
Contributions in 2024	1	0
Expected Minimum Contributions in 2025	1
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	7
2026	8
2027	8
2028	9
2029	9
2030-2034	46
Houston Electric | Mutual funds | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 77	$ 86
Houston Electric | Mutual funds | International equities | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	8.00%	9.00%
Houston Electric | Mutual funds | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	18.00%	19.00%
Houston Electric | Mutual funds | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	74.00%	72.00%
Houston Electric | Mutual funds | Level 1 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 77	$ 86
Houston Electric | Mutual funds | Level 2 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Houston Electric | Mutual funds | Level 3 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
Houston Electric | Benefit Obligation
Postemployment Benefits [Abstract]
Deferred compensation plans	3	3
Split-dollar life insurance arrangements	$ 1	1
Houston Electric | Minimum | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	13.00%
Houston Electric | Minimum | International equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	3.00%
Houston Electric | Minimum | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	69.00%
Houston Electric | Minimum | Cash | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	0.00%
Houston Electric | Maximum | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	23.00%
Houston Electric | Maximum | International equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	13.00%
Houston Electric | Maximum | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	79.00%
Houston Electric | Maximum | Cash | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	2.00%
CERC
Savings Plan [Abstract]
Savings plan benefit expenses	$ 23	20	22
Postemployment Benefits [Abstract]
Deferred compensation plans	0	0	0
CERC | Pension Plan | Qualified pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions in 2024	0
Expected Minimum Contributions in 2025	0
CERC | Pension Plan | Non-qualified pension plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions in 2024	0
Expected Minimum Contributions in 2025	0
CERC | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	26	26	$ 25
Contributions in 2024	5	4
Expected Minimum Contributions in 2025	5
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2025	6
2026	6
2027	7
2028	7
2029	7
2030-2034	35
CERC | Mutual funds | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 26	$ 26
CERC | Mutual funds | International equities | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	7.00%	6.00%
CERC | Mutual funds | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	21.00%	22.00%
CERC | Mutual funds | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, actual allocation (as a percent)	72.00%	71.00%
CERC | Mutual funds | Level 1 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	$ 26	$ 26
CERC | Mutual funds | Level 2 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
CERC | Mutual funds | Level 3 | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan assets, fair value	0	0
CERC | Benefit Obligation
Postemployment Benefits [Abstract]
Deferred compensation plans	1	1
Split-dollar life insurance arrangements	$ 0	$ 0
CERC | Minimum | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	15.00%
CERC | Minimum | International equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	2.00%
CERC | Minimum | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	68.00%
CERC | Minimum | Cash | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	0.00%
CERC | Maximum | U.S. equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	25.00%
CERC | Maximum | International equity | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	12.00%
CERC | Maximum | Fixed income | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	78.00%
CERC | Maximum | Cash | Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocation (as a percent)	2.00%

X

- Definition

Defined Benefit Plan, Fair Value, Obligation, Financial Instrument

+ References

No definition available.

+ Details

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Namespace Prefix:	cnp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Represents the fair value of an obligation to return cash received as collateral from securities lending

+ References

No definition available.

+ Details

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X

- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits, excluding investments measured at net asset value per share or its equivalent.

+ References

No definition available.

+ Details

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Namespace Prefix:	cnp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Represents the maximum percentage allowed of total account balance invested in company stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	cnp_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The number of shares of the entity's common stock held by the savings plan

+ References

No definition available.

+ Details

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Namespace Prefix:	cnp_
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Balance Type:	na
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X

- Definition

This represents the noncurrent liability related to split-dollar life insurance arrangements within other non-qualified plans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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X

- Definition

Percentage of investments held by the Savings Plan in the Entity's common stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	cnp_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
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X

- References

No definition available.

+ Details

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Namespace Prefix:	cnp_
Data Type:	xbrli:stringItemType
Balance Type:	na
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X

- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

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-Topic 710
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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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