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REGULATORY MATTERS - Schedule of Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 4,711 | $ 5,493 |
Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 1,217 | 1,481 |
Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 3,928 | 4,252 |
Costs recovered annually |  | 12 | 12 | $ 2
Storm damage reserves |  | 213 |  |
Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 46 | 136 |
Regulatory asset amortization period | 4 years |  |  |
Regulatory liability amortization period | 3 years |  |  |
Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (1,471) | (1,925) |
Deferred Income Tax Credits |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (5,636) | (6,016) |
Deferred Income Tax Credits | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (1,968) | (2,016) |
Deferred Income Tax Credits | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (2,537) | (2,805) |
Deferred Income Tax Credits | Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory liabilities |  | 220 |  |
Deferred Income Tax Credits | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (288) | (320) |
Regulatory liabilities |  | $ 46 |  |
Deferred Income Tax Credits | Mississippi Power | Retail electric revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory liability amortization period |  | 3 years |  |
Deferred Income Tax Credits | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (816) | (847) |
Other Cost of Removal Obligations |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (1,826) | (1,999) |
Other Cost of Removal Obligations | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (192) | (335) |
Other Cost of Removal Obligations | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 278 | 212 |
Other Cost of Removal Obligations | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (195) | (194) |
Other Cost of Removal Obligations | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (1,683) | (1,649) |
Customer Refunds |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (189) | (56) |
Customer Refunds | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (181) | (50) |
Regulatory liabilities |  | 181 | 50 |
Customer Refunds | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (8) | (6) |
Regulatory liabilities |  |  | 5 |
Customer Refunds | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Customer Refunds | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Fuel Hedging (Realized And Unrealized) Losses |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (176) |  |
Fuel Hedging (Realized And Unrealized) Losses | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (50) |  |
Regulatory liability amortization period |  | 3 years 6 months |  |
Fuel Hedging (Realized And Unrealized) Losses | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (72) |  |
Regulatory liability amortization period |  | 3 years |  |
Fuel Hedging (Realized And Unrealized) Losses | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (54) |  |
Regulatory liability amortization period |  | 3 years |  |
Fuel Hedging (Realized And Unrealized) Losses | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 0 |  |
Storm/Property Damage Reserves |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (133) | (81) |
Storm/Property Damage Reserves | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (103) | (77) |
Storm/Property Damage Reserves | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Storm/Property Damage Reserves | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (30) | (4) |
Storm/Property Damage Reserves | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Over Recovered Regulatory Clause Revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (63) | (185) |
Over Recovered Regulatory Clause Revenues | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (1) | (46) |
Over Recovered Regulatory Clause Revenues | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | (59) | (44) |
Over Recovered Regulatory Clause Revenues | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Over Recovered Regulatory Clause Revenues | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (3) | (95) |
Regulatory liability amortization period |  | 4 years |  |
Other Regulatory Liabilities |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (121) | (149) |
Other Regulatory Liabilities | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (29) | (37) |
Regulatory liability amortization period |  | 16 years |  |
Other Regulatory Liabilities | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (24) | (30) |
Regulatory liability amortization period |  | 11 years |  |
Other Regulatory Liabilities | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (4) | (6) |
Regulatory liability amortization period |  | 3 years |  |
Other Regulatory Liabilities | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ (57) | (54) |
Regulatory liability amortization period |  | 20 years |  |
Excess Deferred Income Tax Liabilities Not Subject to Normalization | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 3 |  |
AROs |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 5,685 | 5,147 |
AROs | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 1,576 | 1,470 |
AROs | Alabama Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 53 years |  |
AROs | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 3,866 | 3,457 |
AROs | Georgia Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 60 years |  |
AROs | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 236 | 212 |
AROs | Mississippi Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 55 years |  |
AROs | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 0 | 0 |
AROs | Southern Company Gas | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 80 years |  |
Retiree Benefit Plans |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 2,998 | 4,958 |
Retiree Benefit Plans | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 747 | 1,265 |
Retiree Benefit Plans | Alabama Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 13 years |  |
Retiree Benefit Plans | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 962 | 1,647 |
Retiree Benefit Plans | Georgia Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 13 years |  |
Retiree Benefit Plans | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 145 | 238 |
Retiree Benefit Plans | Mississippi Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 13 years |  |
Retiree Benefit Plans | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 95 | 187 |
Retiree Benefit Plans | Southern Company Gas | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 14 years |  |
Remaining Net Book Value of Retired Assets |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 1,050 | 1,183 |
Remaining Net Book Value of Retired Assets | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 574 | 632 |
Remaining Net Book Value of Retired Assets | Alabama Power | Plant Gorgas Units 8, 9, And 10 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 533 |  |
Remaining Net Book Value of Retired Assets | Alabama Power | Maximum | Plant Gorgas Units 8, 9, And 10 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 16 years |  |
Remaining Net Book Value of Retired Assets | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 455 | 527 |
Remaining Net Book Value of Retired Assets | Georgia Power | Plant Hammond Units 1 - 4 and Plant Branch Units 2 - 4 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 445 |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Plant McIntosh Unit 1 and Plant Mitchell Unit 3 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 10 |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  |  |  | 3 years
Remaining Net Book Value of Retired Assets | Georgia Power | Maximum | Plant Hammond Units 1 - 4 and Plant Branch Units 2 - 4 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 14 years |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Minimum | Plant Hammond Units 1 - 4 and Plant Branch Units 2 - 4 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 2 years |  |
Remaining Net Book Value of Retired Assets | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 21 | 24 |
Remaining Net Book Value of Retired Assets | Mississippi Power | Plant Watson and Plant Greene County | Wholesale electric revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 10 years |  |
Remaining Net Book Value of Retired Assets | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 0 | 0 |
Deferred Income Tax Charges |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 829 | 801 |
Deferred Income Tax Charges | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 240 | 235 |
Deferred Income Tax Charges | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 555 | 531 |
Deferred Income Tax Charges | Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset |  | 145 |  |
Deferred Income Tax Charges | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 31 | 32 |
Deferred Income Tax Charges | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Under Recovered Regulatory Clause Revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 806 | 185 |
Under Recovered Regulatory Clause Revenues | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 225 | 58 |
Regulatory asset amortization period |  | 8 years |  |
Under Recovered Regulatory Clause Revenues | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 0 | 0 |
Regulatory asset amortization period |  | 2 years |  |
Under Recovered Regulatory Clause Revenues | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 49 | 52 |
Under Recovered Regulatory Clause Revenues | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 532 | 75 |
Regulatory asset amortization period |  | 4 years |  |
Environmental Remediation |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 302 | 310 |
Environmental Remediation | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Environmental Remediation | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 35 | 41 |
Environmental Remediation | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Environmental Remediation | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 267 | 269 |
Loss on Reacquired Debt |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 281 | 304 |
Loss on Reacquired Debt | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 42 | 47 |
Loss on Reacquired Debt | Alabama Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 26 years |  |
Loss on Reacquired Debt | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 231 | 248 |
Loss on Reacquired Debt | Georgia Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 31 years |  |
Loss on Reacquired Debt | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 6 | 6 |
Loss on Reacquired Debt | Mississippi Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 20 years |  |
Loss on Reacquired Debt | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 2 | 3 |
Loss on Reacquired Debt | Southern Company Gas | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 6 years |  |
Vacation Pay |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 207 | 207 |
Regulatory asset amortization period |  | 1 year |  |
Vacation Pay | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 81 | 80 |
Vacation Pay | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 102 | 104 |
Vacation Pay | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 10 | 10 |
Vacation Pay | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 14 | 13 |
Regulatory Clauses |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 142 | 142 |
Regulatory Clauses | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 142 | 142 |
Regulatory Clauses | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Regulatory Clauses | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Regulatory Clauses | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Storm Damage |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 97 | 262 |
Storm Damage | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Storm Damage | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 48 | 262 |
Storm Damage | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 49 | 0 |
Storm Damage | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Long Term Debt Fair Value Adjustment |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 79 | 92 |
Long Term Debt Fair Value Adjustment | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Long Term Debt Fair Value Adjustment | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Long Term Debt Fair Value Adjustment | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Long Term Debt Fair Value Adjustment | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 79 | 92 |
Long Term Debt Fair Value Adjustment | Southern Company Gas | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 17 years |  |
Nuclear Outage |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 75 | 101 |
Nuclear Outage | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 41 | 61 |
Nuclear Outage | Alabama Power | Plant Farley |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 18 months |  |
Nuclear Outage | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 34 | 40 |
Nuclear Outage | Georgia Power | Maximum | Plant Hatch (nuclear) |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 24 months |  |
Nuclear Outage | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 0 | 0 |
Nuclear Outage | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Software and Cloud Computing Costs |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 73 | 31 |
Software and Cloud Computing Costs | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 35 | 17 |
Regulatory asset amortization period |  | 10 years |  |
Software and Cloud Computing Costs | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 33 | 12 |
Software and Cloud Computing Costs | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Software and Cloud Computing Costs | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 5 | 2 |
Regulatory asset amortization period |  | 10 years |  |
Kemper County energy facility assets, net |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 35 | 50 |
Kemper County energy facility assets, net | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Kemper County energy facility assets, net | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Kemper County energy facility assets, net | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 35 | 50 |
Regulatory asset |  | 44 |  |
Regulatory liabilities |  | 9 |  |
Kemper County energy facility assets, net | Mississippi Power | Retail electric revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset |  | 33 |  |
Regulatory liabilities |  | 9 |  |
Kemper County energy facility assets, net | Mississippi Power | Wholesale electric revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset |  | 11 |  |
Kemper County energy facility assets, net | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Plant Daniel Units 3 and 4 |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 28 | 32 |
Plant Daniel Units 3 and 4 | Retail electric revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 19 |  |
Plant Daniel Units 3 and 4 | Wholesale electric revenues |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 9 |  |
Plant Daniel Units 3 and 4 | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Plant Daniel Units 3 and 4 | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Plant Daniel Units 3 and 4 | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 28 | 32 |
Plant Daniel Units 3 and 4 | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 0 | 0 |
Other Regulatory Assets |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 168 | 174 |
Other Regulatory Assets | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 38 | 35 |
Regulatory asset amortization period |  | 23 years |  |
Other Regulatory Assets | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 29 | 56 |
Regulatory asset amortization period |  | 10 years |  |
Other Regulatory Assets | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 7 | 4 |
Regulatory asset amortization period |  | 6 years |  |
Other Regulatory Assets | Southern Company Gas |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 94 | $ 79 |
Regulatory asset amortization period |  | 20 years |  |
CCR AROs | Georgia Power | Maximum |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Regulatory asset amortization period |  | 3 years |  |
Retiree Medicare Drug Subsidy | Alabama Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 7 |  |
Retiree Medicare Drug Subsidy | Georgia Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | 4 |  |
Regulatory Clauses, Amortized Through PEP | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 24 |  |
Regulatory asset amortization period |  | 3 years |  |
Ad Valorem Tax Adjustment Clause | Mississippi Power |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |
Total regulatory assets (liabilities), net |  | $ 25 |  |

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