Debt, Accrued and Unpaid Interest

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt premium.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Short-term Borrowings and Long-term Debt - Debt Repayments and Redemptions (Details) - USD ($) $ in Millions			1 Months Ended	6 Months Ended
	Mar. 31, 2022	Jan. 31, 2022	Mar. 31, 2022	Jun. 30, 2022
Senior Notes \| CERC
Debt Instrument [Line Items]
Aggregate Principal				$ 500
Long-term Debt
Debt Instrument [Line Items]
Aggregate Principal				1,030
Long-term Debt \| CERC
Debt Instrument [Line Items]
Aggregate Principal				$ 425
CERC Senior Notes Floating Rate due 2023 \| Senior Notes \| CERC \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)				0.50%
CERC Senior Notes Floating Rate due 2023 \| Long-term Debt \| Senior Notes \| CERC
Debt Instrument [Line Items]
Aggregate Principal				$ 425
Outstanding debt balance		$ 1,000
Debt instrument, redemption price (as a percent)		100.00%
CNP First Mortgage Bonds Due 2022 \| Long-term Debt \| First Mortgage Bonds
Debt Instrument [Line Items]
Aggregate Principal				$ 5
Interest rate of debt (as a percent)				0.82%
CNP Senior Note 3.85% Due 2024 \| Long-term Debt \| Senior Notes
Debt Instrument [Line Items]
Aggregate Principal				$ 250
Interest rate of debt (as a percent)				3.85%
Debt instrument, redemption price (as a percent)	100.00%
Accrued and unpaid interest	$ 2		$ 2
Write off of issuance costs			1
Make-whole premium	7		7
Total redemption price			260
CNP Senior Notes Due 2028 \| Long-term Debt \| Senior Notes
Debt Instrument [Line Items]
Aggregate Principal	350		350	$ 350
Interest rate of debt (as a percent)				4.25%
Outstanding debt balance	$ 500		500
Debt instrument, redemption price (as a percent)	100.00%
Accrued and unpaid interest	$ 6		6
Write off of issuance costs	3
Make-whole premium	34		$ 34
Total redemption price	$ 393