Regulatory Matters - Alabama Power (Details) - ALABAMA POWER CO - Restatement Adjustment $ in Millions	Apr. 15, 2019 USD ($)
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Capitalized asset retirement costs, net	$ 700
Remaining amounts of regulatory assets for which no return on investment during recovery period is provided	700
Plant Gorgas Units 8, 9, and 10
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net investment costs	654
Remaining amounts of regulatory assets for which no return on investment during recovery period is provided	$ 654

Public Utilities, Net Investment Costs To Be Transferred Upon Retirement

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The amount of asset retirement costs previously incurred and capitalized separately from the capitalized amount of the associated long-lived assets.

+ References

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Remaining balance of regulatory assets for which no return on investment during recovery is provided. In some cases, a regulator may permit an enterprise to include a cost that would be charged to expense by an unregulated enterprise as an allowable cost over a period of time by amortizing that cost for rate-making purposes, but the regulator does not include the unrecovered amount in the rate base.

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-Publisher FASB
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-Topic 980
-SubTopic 340
-Section 50
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