Fair Value Measurements, Including Derivatives (Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis and Included in Level 3) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Regulatory Assets
Beginning balance	$ 225	$ 0	$ 148	$ 0
Included in earnings:
Purchased power	15	0	18	0
Settlements	(15)	0	(18)	0
Ending balance	295	(13)	295	(13)
Other Regulatory Assets Liabilities
Included in earnings:
Included in regulatory assets/liabilities	$ 70	$ (13)	$ 147	$ (13)

Costs of power used for operations in prior periods that were expected to be recovered from customers in future periods.

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-Publisher FASB
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Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) included in earnings for investments classified as other.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
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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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