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REGULATORY MATTERS - Schedule of Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions |  | 12 Months Ended | 24 Months Ended |  |
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Jan. 01, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2022 | Sep. 30, 2022 | Dec. 31, 2020
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 6,523 | $ 5,833 |  | $ 5,833 |  |
Regulatory asset amortization period |  | 4 years |  |  |  |  |
Regulatory asset |  | $ 66 | 216 |  | 216 |  |
Plant In Service Net Of Depreciation |  | (90,703) | (82,232) |  | (82,232) |  |
Other Regulatory Assets Current |  | 1,120 | 860 |  | 860 |  |
Revision of Prior Period, Reclassification, Adjustment |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Plant In Service Net Of Depreciation |  |  | 42 |  | 42 | $ 600 |
Other Regulatory Assets Current |  |  | 42 |  | 42 |  |
Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 2,720 | 2,340 |  | 2,340 |  |
Customer refund |  | 304 |  |  |  |  |
Regulatory asset |  | 76 | 97 |  | 97 |  |
Plant In Service Net Of Depreciation |  | (24,298) | (23,002) |  | (23,002) |  |
Other Regulatory Assets Current |  | 385 | 372 |  | 372 |  |
Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 5,090 | 4,663 |  | 4,663 |  |
Regulatory asset |  |  | 83 |  | 83 |  |
Regulatory liabilities |  | 54 | 83 |  | 83 |  |
Costs recovered annually |  | 5 | 12 | $ 12 |  |  |
Storm damage reserves | $ 31 |  |  |  | 213 |  |
Plant In Service Net Of Depreciation |  | (35,415) | (28,764) |  | (28,764) |  |
Other Regulatory Assets Current |  | 423 | 324 |  | 324 |  |
Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 90 | 4 |  | 4 |  |
Regulatory asset |  | 44 | 36 |  | 36 |  |
Plant In Service Net Of Depreciation |  | (3,731) | (3,565) |  | (3,565) |  |
Other Regulatory Assets Current |  | 56 | 72 |  | 72 |  |
Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (2,225) | (1,891) |  | (1,891) |  |
Plant In Service Net Of Depreciation |  | (15,306) | (14,447) |  | (14,447) |  |
Other Regulatory Assets Current |  | 141 | 119 |  | 119 |  |
Deferred Income Tax Credits |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (4,686) | (5,251) |  | (5,251) |  |
Deferred Income Tax Credits | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (1,506) | (1,925) |  | (1,925) |  |
Deferred Income Tax Credits | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (2,161) | (2,244) |  | (2,244) |  |
Deferred Income Tax Credits | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (241) | (269) |  | (269) |  |
Regulatory liabilities |  | 11 |  |  |  |  |
Deferred Income Tax Credits | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (759) | (788) |  | (788) |  |
Other Cost of Removal Obligations |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (1,312) | (64) |  | (64) |  |
Other Cost of Removal Obligations | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 28 | 0 |  | 0 |  |
Other Cost of Removal Obligations | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 617 | (38) |  | (38) |  |
Other Cost of Removal Obligations | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (186) | 0 |  | 0 |  |
Other Cost of Removal Obligations | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (1,771) | (26) |  | (26) |  |
Over Recovered Regulatory Clause Revenues |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (287) | (1,430) |  | (1,430) |  |
Over Recovered Regulatory Clause Revenues | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (3) | 11 |  | 11 |  |
Over Recovered Regulatory Clause Revenues | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (46) | 462 |  | 462 |  |
Over Recovered Regulatory Clause Revenues | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | (196) |  | (196) |  |
Over Recovered Regulatory Clause Revenues | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ (238) | (1,707) |  | (1,707) |  |
Regulatory liability amortization period |  | 5 years |  |  |  |  |
Reliability reserves |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ (179) | (191) |  | (191) |  |
Reliability reserves | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (143) | (166) |  | (166) |  |
Reliability reserves | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Reliability reserves | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (36) | (25) |  | (25) |  |
Reliability reserves | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Storm/Property Damage Reserves |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (120) | (216) |  | (216) |  |
Storm/Property Damage Reserves | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (76) | (97) |  | (97) |  |
Storm/Property Damage Reserves | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | (83) |  | (83) |  |
Storm/Property Damage Reserves | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (44) | (36) |  | (36) |  |
Storm/Property Damage Reserves | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Customer Refunds |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (19) | (183) |  | (183) |  |
Customer Refunds | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (15) | (62) |  | (62) |  |
Regulatory liabilities |  | 15 | 62 |  | 62 |  |
Customer Refunds | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (4) | (121) |  | (121) |  |
Regulatory liabilities |  |  | 119 |  | 119 |  |
Customer Refunds | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Customer Refunds | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Fuel Hedging (Realized And Unrealized) gains |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (6) |  |  |  |  |
Fuel Hedging (Realized And Unrealized) gains | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (5) |  |  |  |  |
Fuel Hedging (Realized And Unrealized) gains | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (1) |  |  |  |  |
Fuel Hedging (Realized And Unrealized) gains | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  |  |  |  |  |  |
Fuel Hedging (Realized And Unrealized) gains | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 |  |  |  |  |
Other Regulatory Liabilities |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | (308) | (239) |  | (239) |  |
Other Regulatory Liabilities | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ (74) | (40) |  | (40) |  |
Regulatory liability amortization period |  | 11 years |  |  |  |  |
Other Regulatory Liabilities | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ (18) | (21) |  | (21) |  |
Regulatory liability amortization period |  | 9 years |  |  |  |  |
Other Regulatory Liabilities | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ (2) | (3) |  | (3) |  |
Regulatory liability amortization period |  | 4 years |  |  |  |  |
Other Regulatory Liabilities | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ (101) | (93) |  | (93) |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 1 |  |  |  |  |
Fuel Hedging (Realized And Unrealized) losses |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  |  | (83) |  | (83) |  |
Fuel Hedging (Realized And Unrealized) losses | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  |  | (38) |  | (38) |  |
Regulatory liability amortization period |  | 3 years 6 months |  |  |  |  |
Fuel Hedging (Realized And Unrealized) losses | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  |  | (21) |  | (21) |  |
Regulatory liability amortization period |  | 3 years |  |  |  |  |
Fuel Hedging (Realized And Unrealized) losses | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  |  | (24) |  | (24) |  |
Regulatory liability amortization period |  | 4 years |  |  |  |  |
Fuel Hedging (Realized And Unrealized) losses | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  |  | 0 |  | 0 |  |
AROs |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 5,733 | 6,096 |  | 6,096 |  |
AROs | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 1,936 | 1,971 |  | 1,971 |  |
AROs | Alabama Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 64 years |  |  |  |  |
AROs | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 3,505 | 3,829 |  | 3,829 |  |
AROs | Georgia Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 56 years |  |  |  |  |
AROs | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 247 | 242 |  | 242 |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 0 | 0 |  | 0 |  |
AROs | Southern Company Gas | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 85 years |  |  |  |  |
Retiree Benefit Plans |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 3,011 | 2,517 |  | 2,517 |  |
Retiree Benefit Plans | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 815 | 675 |  | 675 |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 976 | 848 |  | 848 |  |
Retiree Benefit Plans | Georgia Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 14 years |  |  |  |  |
Retiree Benefit Plans | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 140 | 113 |  | 113 |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 146 | 114 |  | 114 |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 1,357 | 1,543 |  | 1,543 |  |
Remaining Net Book Value of Retired Assets | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 499 | 562 |  | 562 |  |
Remaining Net Book Value of Retired Assets | Alabama Power | Plant Gorgas Units 8, 9, And 10 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 451 |  |  |  |  |
Remaining Net Book Value of Retired Assets | Alabama Power | Plant Barry Unit 4 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 39 |  |  |  |  |
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 |  | 14 years |  |  |  |  |
Remaining Net Book Value of Retired Assets | Alabama Power | Maximum | Plant Barry Unit 4 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 11 years |  |  |  |  |
Remaining Net Book Value of Retired Assets | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 841 | $ 962 |  | $ 962 |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Plant Wansley Units 1 and 2 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 488 |  |  |  |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | 339 |  |  |  |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Plant Branch Unit 4 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 8 |  |  |  |  |
Remaining Net Book Value of Retired Assets | Georgia Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  |  | 3 years |  | 3 years |  | 4 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 |  | 12 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 |  | 1 year |  |  |  |  |
Remaining Net Book Value of Retired Assets | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 17 | $ 19 |  | $ 19 |  |
Remaining Net Book Value of Retired Assets | Mississippi Power | Plant Watson and Plant Greene County | Retail electric revenues |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 10 years |  |  |  |  |
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 |  | 14 years |  |  |  |  |
Remaining Net Book Value of Retired Assets | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 0 | 0 |  | 0 |  |
Deferred Income Tax Charges |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 897 | 866 |  | 866 |  |
Deferred Income Tax Charges | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 262 | 250 |  | 250 |  |
Deferred Income Tax Charges | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 605 | 583 |  | 583 |  |
Deferred Income Tax Charges | Georgia Power | Plant Vogtle Units 3 and 4 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 17 |  |  |  |  |
Regulatory asset amortization period |  | 10 years |  |  |  |  |
Regulatory asset |  | $ 145 |  |  |  |  |
Deferred Income Tax Charges | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 28 | 30 |  | 30 |  |
Deferred Income Tax Charges | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Under Recovered Regulatory Clause Revenues |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 413 | 953 |  | 953 |  |
Under Recovered Regulatory Clause Revenues | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 381 | 788 |  | 788 |  |
Under Recovered Regulatory Clause Revenues | Alabama Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 7 years |  |  |  |  |
Under Recovered Regulatory Clause Revenues | Alabama Power | Minimum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 1 year |  |  |  |  |
Under Recovered Regulatory Clause Revenues | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 0 | 0 |  | 0 |  |
Regulatory asset amortization period |  | 2 years |  |  |  |  |
Under Recovered Regulatory Clause Revenues | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 12 | 31 |  | 31 |  |
Under Recovered Regulatory Clause Revenues | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 20 | 134 |  | 134 |  |
Regulatory asset amortization period |  | 5 years |  |  |  |  |
Fuel Hedging (Realized And Unrealized) losses |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 270 | 60 |  | 60 |  |
Fuel Hedging (Realized And Unrealized) losses | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 100 | 15 |  | 15 |  |
Regulatory asset amortization period | 5 years |  |  |  |  |  |
Fuel Hedging (Realized And Unrealized) losses | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 121 | 45 |  | 45 |  |
Fuel Hedging (Realized And Unrealized) losses | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 49 | 0 |  | 0 |  |
Fuel Hedging (Realized And Unrealized) losses | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Regulatory asset amortization period | 2 years |  |  |  |  |  |
Deferred Depreciation |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 270 |  |  |  |  |
Deferred Depreciation | Plant Scherer Units 1 through 3 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 70 |  |  |  |  |
Regulatory asset amortization period |  | 6 years |  |  |  |  |
Deferred Depreciation | Plant Bowen Units 1 and 2 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 40 |  |  |  |  |
Deferred Depreciation | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 143 |  |  |  |  |
Deferred Depreciation | Alabama Power | Plant Barry Unit 5 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 57 |  |  |  |  |
Deferred Depreciation | Alabama Power | Plant Barry |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 24 |  |  |  |  |
Deferred Depreciation | Alabama Power | Plant Gaston Unit 5 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 62 |  |  |  |  |
Deferred Depreciation | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 127 |  |  |  |  |
Deferred Depreciation | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 |  |  |  |  |
Deferred Depreciation | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 |  |  |  |  |
Environmental Remediation |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 255 | 294 |  | 294 |  |
Environmental Remediation | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Environmental Remediation | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 20 | 25 |  | 25 |  |
Environmental Remediation | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Environmental Remediation | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 235 | 269 |  | 269 |  |
Loss on Reacquired Debt |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 238 | 257 |  | 257 |  |
Loss on Reacquired Debt | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 35 | 38 |  | 38 |  |
Loss on Reacquired Debt | Alabama Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 24 years |  |  |  |  |
Loss on Reacquired Debt | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 197 | 213 |  | 213 |  |
Loss on Reacquired Debt | Georgia Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 29 years |  |  |  |  |
Loss on Reacquired Debt | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 5 | 5 |  | 5 |  |
Loss on Reacquired Debt | Mississippi Power | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 18 years |  |  |  |  |
Loss on Reacquired Debt | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 1 | 1 |  | 1 |  |
Loss on Reacquired Debt | Southern Company Gas | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 4 years |  |  |  |  |
Vacation Pay |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 217 | 212 |  | 212 |  |
Regulatory asset amortization period |  | 1 year |  |  |  |  |
Vacation Pay | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 83 | 82 |  | 82 |  |
Vacation Pay | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 107 | 108 |  | 108 |  |
Vacation Pay | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 11 | 10 |  | 10 |  |
Vacation Pay | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 16 | 12 |  | 12 |  |
Software and Cloud Computing Costs |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 150 | 111 |  | 111 |  |
Regulatory asset amortization period |  | 5 years |  |  |  |  |
Software and Cloud Computing Costs | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 59 | 46 |  | 46 |  |
Regulatory asset amortization period |  | 10 years |  |  |  |  |
Software and Cloud Computing Costs | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 84 | 59 |  | 59 |  |
Software and Cloud Computing Costs | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 2 | 0 |  | 0 |  |
Software and Cloud Computing Costs | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 5 | 6 |  | 6 |  |
Regulatory asset amortization period |  | 10 years |  |  |  |  |
Regulatory Clauses |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 140 | 142 |  | 142 |  |
Regulatory Clauses | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 112 | 142 |  | 142 |  |
Regulatory Clauses | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Regulatory Clauses | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Regulatory Clauses | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 28 | 0 |  | 0 |  |
Storm Damage |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 92 | 44 |  | 44 |  |
Storm Damage | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Storm Damage | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 54 | 0 |  | 0 |  |
Storm Damage | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 38 | 44 |  | 44 |  |
Regulatory asset amortization period |  | 7 years |  |  |  |  |
Storm Damage | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 0 | 0 |  | 0 |  |
Nuclear Outage |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 83 | 82 |  | 82 |  |
Nuclear Outage | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 50 | 52 |  | 52 |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 33 | 30 |  | 30 |  |
Nuclear Outage | Georgia Power | Maximum | Plant Hatch (nuclear) Units 1 and 2 |  |  |  |  |  |  |
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] |  |  |  |  |  |  |
Net regulatory assets |  | $ 0 | 0 |  | 0 |  |
Nuclear Outage | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Long Term Debt Fair Value Adjustment |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 60 | 69 |  | 69 |  |
Long Term Debt Fair Value Adjustment | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Long Term Debt Fair Value Adjustment | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Long Term Debt Fair Value Adjustment | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Long Term Debt Fair Value Adjustment | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 60 | 69 |  | 69 |  |
Long Term Debt Fair Value Adjustment | Southern Company Gas | Maximum |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 15 years |  |  |  |  |
Qualifying Repairs Of Natural Gas Distribution Systems |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 40 | 26 |  | 26 |  |
Qualifying Repairs Of Natural Gas Distribution Systems | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Qualifying Repairs Of Natural Gas Distribution Systems | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Qualifying Repairs Of Natural Gas Distribution Systems | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Qualifying Repairs Of Natural Gas Distribution Systems | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 40 | 26 |  | 26 |  |
Qualifying Repairs Of Natural Gas Distribution Systems | Atlanta Gas Light |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 20 years |  |  |  |  |
Plant Daniel Units 3 and 4 |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 25 | 27 |  | 27 |  |
Plant Daniel Units 3 and 4 | Retail electric revenues |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 17 |  |  |  |  |
Plant Daniel Units 3 and 4 | Wholesale electric revenues |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 8 |  |  |  |  |
Plant Daniel Units 3 and 4 | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Plant Daniel Units 3 and 4 | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Plant Daniel Units 3 and 4 | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 25 | 27 |  | 27 |  |
Plant Daniel Units 3 and 4 | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Kemper County energy facility assets, net |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 7 | 20 |  | 20 |  |
Kemper County energy facility assets, net | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Kemper County energy facility assets, net | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Kemper County energy facility assets, net | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 7 | 20 |  | 20 |  |
Regulatory asset |  | 9 |  |  |  |  |
Regulatory liabilities |  | 2 |  |  |  |  |
Kemper County energy facility assets, net | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 0 | 0 |  | 0 |  |
Other Regulatory Assets |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | 182 | 171 |  | 171 |  |
Other Regulatory Assets | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 39 | 36 |  | 36 |  |
Regulatory asset amortization period |  | 20 years |  |  |  |  |
Other Regulatory Assets | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 33 | 27 |  | 27 |  |
Regulatory asset amortization period |  | 10 years |  |  |  |  |
Other Regulatory Assets | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 18 | 16 |  | 16 |  |
Regulatory asset amortization period |  | 14 years |  |  |  |  |
Other Regulatory Assets | Southern Company Gas |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 93 | $ 92 |  | $ 92 |  |
Regulatory asset amortization period |  | 15 years |  |  |  |  |
CCR AROs | Alabama Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period |  | 38 years |  |  |  |  |
CCR AROs | Georgia Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory asset amortization period | 4 years | 3 years |  |  |  |  |
Regulatory Clauses, Amortized Through PEP | Mississippi Power |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |
Net regulatory assets |  | $ 12 |  |  |  |  |

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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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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 340 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481878/980-340-50-1 + Details
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- Definition The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 405 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481854/980-405-25-1 + Details
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- Definition Amortization period for the recovery of regulatory liability, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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