Selected Balance Sheet Data Selected Balance Sheet Data, Inventories (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Public Utilities, Inventory [Line Items]
Total inventories	$ 645	$ 631
Materials and supplies
Public Utilities, Inventory [Line Items]
Inventories	309	289
Fuel
Public Utilities, Inventory [Line Items]
Inventories	216	182
Natural gas
Public Utilities, Inventory [Line Items]
Inventories	$ 120	$ 160

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://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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