Selected Balance Sheet Data Balance Sheet Related Disclosures, Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Public Utilities, Inventory [Line Items]
Total inventories	$ 311	$ 277
Materials and supplies
Public Utilities, Inventory [Line Items]
Inventories	178	136
Fuel
Public Utilities, Inventory [Line Items]
Inventories	67	64
Natural gas
Public Utilities, Inventory [Line Items]
Inventories	$ 66	$ 77

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

Reference 1: 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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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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