Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Public Utilities, Inventory [Line Items]
Inventories	$ 336	$ 384
Materials and supplies
Public Utilities, Inventory [Line Items]
Inventories	214	200
Fuel
Public Utilities, Inventory [Line Items]
Inventories	92	103
Natural Gas
Public Utilities, Inventory [Line Items]
Inventories	$ 30	$ 81

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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