The dollar denomination for each individual note

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- Definition

Long Term Debt, Contingent Principal Amount

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- Definition

Number of shares attributable to each note and referenced in determining the fair value of the cash to be exchange at behest of note holder.

+ References

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- Definition

Sale Of Stock, Shares Received

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No definition available.

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- Definition

The amount of cash each $1,000 original principal amount of ZENS can be exchanged for a the behest of the note holder.

+ References

No definition available.

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- Definition

The percentage of the fair value of the referenced TW Common shares attributable to each note and the percentage of composite fair value each note can be exchanged for cash.

+ References

No definition available.

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- Definition

The target annual yield from interest and cash dividends on reference shares, before any adjustment to increase or decrease principal amount of subordinated note is made.

+ References

No definition available.

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- 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.

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- Definition

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

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- Definition

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

+ References

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of investment in marketable security, classified as current.

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

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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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No definition available.

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Equity Securities and Indexed Debt Securities (ZENS) (CenterPoint Energy) - Narrative (Details)		12 Months Ended
	Apr. 08, 2022 shares	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Unrealized gains (loss) on equity securities		$ (313,000,000)	$ (52,000,000)	$ 49,000,000
Target annual yield on reference shares		2.309%
Investment in equity securities		$ 510,000,000	1,439,000,000
AT&T
Debt and Equity Securities, FV-NI [Line Items]
Shares expected to be received \| shares	0.241917
Ownership (percentage)	71.00%
ZENS-Related Securities
Debt and Equity Securities, FV-NI [Line Items]
Investment in equity securities		507,000,000	$ 820,000,000	$ 871,000,000	$ 822,000,000
ZENS debt
Debt and Equity Securities, FV-NI [Line Items]
Principal amount of debt issued		1,000,000,000
Long-term debt, gross		$ 828,000,000
Subordinated note cash exchangeable percentage of fair value		95.00%
Debt instrument interest rate (as a percent)		2.00%
Contingent principal amount		$ 26,000,000
The cash exchange amount from referenced shares per $1,000 face amount of individual notes		582
Face amount of each indexed debt security notes issued by CenterPoint Energy in September 1999		$ 1,000
ZENS debt \| AT&T Common
Debt and Equity Securities, FV-NI [Line Items]
Number of shares referenced in exchangeable subordinated note \| shares	0.7185	0.7185	0.7185
ZENS debt \| Charter Common
Debt and Equity Securities, FV-NI [Line Items]
Number of shares referenced in exchangeable subordinated note \| shares	0.061382	0.061382	0.061382
ZENS debt \| WBD Common
Debt and Equity Securities, FV-NI [Line Items]
Number of shares referenced in exchangeable subordinated note \| shares	0.173817