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REGULATORY MATTERS - GPC Fuel Cost and Storm Damage Recovery (Details) - USD ($) $ in Millions |  | 1 Months Ended | 4 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Nov. 18, 2021 | May 31, 2020 | Sep. 30, 2020 | Dec. 31, 2021 | Dec. 31, 2020
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Net regulatory assets |  |  |  | $ 4,711 | $ 5,493
Other regulatory assets |  |  |  | 653 | 810
Other regulatory assets, deferred |  |  |  | 5,577 | 7,198
Georgia Power |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Approved decrease in annual billing based on fuel cost recovery rate |  | $ 740 |  |  |
Approved decrease in annual billing based on fuel cost recovery rate, term |  | 2 years |  |  |
Public utilities, approved rate increase (decrease), amount | $ 252 |  | $ (44) |  |
Approved rate increase, percent | 15.00% |  |  |  |
Adjustment to fuel cost recovery rate if under recovered fuel balance exceeds budget thereafter |  |  |  | 200 |
Over (under) recovered fuel balance |  |  |  | $ (410) | 113
Required period for options and hedges |  |  |  | 36 months |
Storm damage reserves |  |  |  | $ 213 |
Net regulatory assets |  |  |  | 3,928 | 4,252
Other regulatory assets |  |  |  | 241 | 248
Other regulatory assets, deferred |  |  |  | 1,964 | 2,692
Georgia Power | Storm damage reserves |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Net regulatory assets |  |  |  | 48 | 262
Georgia Power | Storm/Property Damage Reserves |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Other regulatory assets |  |  |  | $ 48 | 213
Other regulatory assets, deferred |  |  |  |  | $ 49

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- Definition Approved increase (decrease) in annual billing based on fuel cost recovery rate. + References No definition available. + Details
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- Definition Carrying amount of other regulatory assets (not elsewhere included) as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References No definition available. + Details
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