Selected Balance Sheet Data Selected Balance Sheet Data, Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Public Utilities, Inventory [Line Items]
Total inventories	$ 688	$ 803
Materials and supplies
Public Utilities, Inventory [Line Items]
Inventories	368	330
Fuel
Public Utilities, Inventory [Line Items]
Inventories	193	201
Natural gas
Public Utilities, Inventory [Line Items]
Inventories	$ 127	$ 272

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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-Topic 852
-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The period end amount for a type of inventory held by the utility in a schedule of inventories.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 10
-Name Accounting Standards Codification
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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

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