Stock Based Compensation (Accrual Adjustments) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Compensation Costs included in O&M Expense	$ 28	$ 35	$ 33
Income Tax Benefit Recognized in Consolidated Statement of Operations	8	10	9
Excess Tax Benefits	$ 2	$ 2	$ 5

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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-Publisher FASB
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