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PROPERTY, PLANT, AND EQUIPMENT - Ownership and Investment in Jointly-Owned Facilities (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) mi
Alabama Power |
Other Ownership Interests [Line Items] |
Percent Ownership | 14.00%
Alabama Power | Greene County (natural gas) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 60.00%
Plant in Service | $ 191
Accumulated Depreciation | 113
CWIP | $ 1
Alabama Power | Plant Miller (coal) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 91.80%
Plant in Service | $ 2,156
Accumulated Depreciation | 778
CWIP | $ 40
Georgia Power | Plant Hatch (nuclear) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 50.10%
Plant in Service | $ 1,446
Accumulated Depreciation | 659
CWIP | $ 70
Georgia Power | Plant Vogtle (nuclear) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 45.70%
Plant in Service | $ 3,664
Accumulated Depreciation | 2,331
CWIP | $ 62
Georgia Power | Plant Vogtle (nuclear) Units 3 and 4 |
Other Ownership Interests [Line Items] |
Percent Ownership | 45.70%
Plant in Service | $ 4,613
Accumulated Depreciation | 19
CWIP | $ 3,232
Georgia Power | Plant Scherer (coal) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 8.40%
Plant in Service | $ 287
Accumulated Depreciation | 123
CWIP | $ 2
Georgia Power | Plant Scherer (coal) Unit 3 |
Other Ownership Interests [Line Items] |
Percent Ownership | 75.00%
Plant in Service | $ 1,310
Accumulated Depreciation | 639
CWIP | $ 10
Georgia Power | Rocky Mountain (pumped storage) |
Other Ownership Interests [Line Items] |
Percent Ownership | 25.40%
Plant in Service | $ 181
Accumulated Depreciation | 153
CWIP | $ 0
Mississippi Power | Greene County (natural gas) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 40.00%
Plant in Service | $ 125
Accumulated Depreciation | 80
CWIP | $ 0
Mississippi Power | Plant Daniel (coal) Units 1 and 2 |
Other Ownership Interests [Line Items] |
Percent Ownership | 50.00%
Plant in Service | $ 805
Accumulated Depreciation | 281
CWIP | $ 1
Southern Company Gas | Dalton Pipeline (natural gas pipeline) |
Other Ownership Interests [Line Items] |
Percent Ownership | 50.00%
Plant in Service | $ 271
Accumulated Depreciation | 27
CWIP | $ 0
Pipeline infrastructure (miles) | mi | 115
Agreement to lease undivided ownership (percent) | 50.00%
Future minimum payments receivable | $ 26

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- Definition The period end amount owned by the reporting utility of a jointly owned utility plant in service. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479960/980-360-S99-1 + Details
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- Definition The period end amount of construction work in progress at a jointly owned electricity generation plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479960/980-360-S99-1 + Details
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- Definition The period end amount of accumulated depreciation in a jointly owned electricity generation plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479960/980-360-S99-1 + Details
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