Fair Value of Financial Assets and Liabilities - Consideration of Credit Risk Concentrations (Details) - Credit Concentration Risk $ in Millions	Sep. 30, 2023 USD ($) Counterparty
Derivative [Line Items]
Significant counterparties	10
Municipal or cooperative electric entities or other utilities
Derivative [Line Items]
Significant counterparties	9
External credit rating, investment grade
Derivative [Line Items]
Significant counterparties	4
Credit exposure \| $	$ 10
Credit exposure, percentage	30.00%
Internal investment grade
Derivative [Line Items]
Significant counterparties	5
Credit exposure \| $	$ 23
Credit exposure, percentage	69.00%
External Credit Rating, Non Investment Grade [Member]
Derivative [Line Items]
Significant counterparties	1
Credit exposure, percentage	1.00%

Number of the entity's most significant counterparties for wholesale, trading and non-trading commodity activities with credit exposure.

No definition available.

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- Definition

Percentage of wholesale, trading and non-trading commodity credit exposure for the entity's most significant counterparties.

+ References

No definition available.

+ Details

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- Definition

Wholesale, trading and non-trading commodity credit exposure for the entity's most significant counterparties.

+ References

No definition available.

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- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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