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VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Provision for uncollectible accounts: |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | $ 71 | $ 78 | $ 118 |
Charged to Income | 87 | 71 | 51 |
Charged to Other Accounts | 3 | (1) | (23) |
Deductions | 93 | 77 | 68 |
Balance at End of Period | 68 | 71 | 78 | $ 118
Provision for uncollectible accounts: | Alabama Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 14 | 14 | 43 |
Charged to Income | 16 | 10 | (7) |
Charged to Other Accounts | 0 | 0 | 0 |
Deductions | 14 | 10 | 22 |
Balance at End of Period | 16 | 14 | 14 | 43
Provision for uncollectible accounts: | Georgia Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 3 | 2 | 26 |
Charged to Income | 26 | 21 | 16 |
Charged to Other Accounts | 0 | 0 | (23) | 23
Deductions | 25 | 20 | 17 |
Balance at End of Period | 4 | 3 | 2 | 26
Provision for uncollectible accounts: | Mississippi Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 1 | 1 | 1 |
Charged to Income | 2 | 1 | 1 |
Charged to Other Accounts | 0 | 1 | 0 |
Deductions | 2 | 2 | 1 |
Balance at End of Period | 1 | 1 | 1 | 1
Provision for uncollectible accounts: | Southern Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 1 | 5 | 0 |
Charged to Income | 0 | (2) | 5 |
Charged to Other Accounts | 0 | 0 | 0 |
Deductions | 0 | 2 | 0 |
Balance at End of Period | 1 | 1 | 5 | 0
Provision for uncollectible accounts: | Southern Company Gas |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 50 | 39 | 40 |
Charged to Income | 43 | 55 | 26 |
Charged to Other Accounts | 3 | 0 | 0 |
Deductions | 52 | 44 | 27 |
Balance at End of Period | 44 | 50 | 39 | 40
Tax valuation allowance (net state) |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 207 | 169 | 112 |
Charged to Income | (14) | 68 | 57 |
Charged to Other Accounts | (25) | (30) | 0 |
Deductions | 0 | 0 | 0 |
Balance at End of Period | 168 | 207 | 169 | 112
Tax valuation allowance (net state) | Georgia Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 98 | 58 | 28 |
Charged to Income | (15) | 70 | 30 |
Charged to Other Accounts | (23) | (30) | 0 |
Deductions | 0 | 0 | 0 |
Balance at End of Period | 60 | 98 | 58 | 28
Tax valuation allowance (net state) | Mississippi Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 32 | 32 | 32 |
Charged to Income | 0 | 0 | 0 |
Charged to Other Accounts | 0 | 0 | 0 |
Deductions | 0 | 0 | 0 |
Balance at End of Period | 32 | 32 | 32 | 32
Tax valuation allowance (net state) | Southern Power |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 21 | 21 | 27 |
Charged to Income | 0 | 0 | (6) |
Charged to Other Accounts | 0 | 0 | 0 |
Deductions | 0 | 0 | 0 |
Balance at End of Period | 21 | 21 | 21 | 27
Tax valuation allowance (net state) | Southern Company Gas |  |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |  |
Balance at Beginning of Period | 7 | 7 | 4 |
Charged to Income | 0 | 0 | 3 |
Charged to Other Accounts | (2) | 0 | 0 |
Deductions | 0 | 0 | 0 |
Balance at End of Period | $ 5 | $ 7 | $ 7 | $ 4

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