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FINANCING (Tables) | 12 Months Ended
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Dec. 31, 2023
Debt Disclosure [Abstract] |
Summary of long-term debt | Details of long-term debt at December 31, 2023 and 2022 are provided in the following table:
| At December 31, 2023 |  | Balance Outstanding at December 31,
| Maturity |  | Weighted Average Interest Rate |  | 2023 |  | 2022
|  |  |  |  | (in millions)
Southern Company |  |  |  |  |  |  |
Senior notes(a) | 2024-2073 |  | 4.16% |  | $ | 40,235 |  |  | $ | 35,683 |
Junior subordinated notes | 2024-2081 |  | 4.33% |  | 8,333 |  |  | 8,836 |
FFB loans(b) | 2024-2044 |  | 2.88% |  | 4,788 |  |  | 4,874 |
Revenue bonds(c) | 2024-2063 |  | 3.77% |  | 3,400 |  |  | 2,844 |
First mortgage bonds(d) | 2025-2063 |  | 3.64% |  | 2,500 |  |  | 2,275 |
Medium-term notes | 2026-2027 |  | 7.03% |  | 84 |  |  | 84 |
Other long-term debt | 2024-2045 |  | 5.44% |  | 234 |  |  | 167 |
Finance lease obligations(e) |  |  |  |  | 298 |  |  | 314 |
Unamortized fair value adjustment |  |  |  |  | 302 |  |  | 330 |
Unamortized debt premium (discount), net |  |  |  |  | (198) |  |  | (193) |
Unamortized debt issuance expenses |  |  |  |  | (290) |  |  | (273) |
Total long-term debt |  |  |  |  | 59,686 |  |  | 54,941 |
Less: Amount due within one year |  |  |  |  | 2,476 |  |  | 4,285 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 57,210 |  |  | $ | 50,656 |
Alabama Power |  |  |  |  |  |  |
Senior notes | 2025-2073 |  | 3.95% |  | $ | 9,875 |  |  | $ | 9,675 |
Revenue bonds(c) | 2024-2063 |  | 3.94% |  | 1,321 |  |  | 995 |
Other long-term debt | 2026-2030 |  | 7.04% |  | 75 |  |  | 45 |
Finance lease obligations(e) |  |  |  |  | 5 |  |  | 5 |
Unamortized debt premium (discount), net |  |  |  |  | (20) |  |  | (18) |
Unamortized debt issuance expenses |  |  |  |  | (73) |  |  | (72) |
Total long-term debt |  |  |  |  | 11,183 |  |  | 10,630 |
Less: Amount due within one year |  |  |  |  | 223 |  |  | 301 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 10,960 |  |  | $ | 10,329 |
Georgia Power |  |  |  |  |  |  |
Senior notes | 2024-2052 |  | 4.34% |  | $ | 9,575 |  |  | $ | 7,925 |
Junior subordinated notes | 2077 |  | 5.00% |  | 270 |  |  | 270 |
FFB loans(b) | 2024-2044 |  | 2.88% |  | 4,788 |  |  | 4,874 |
Revenue bonds(c) | 2025-2062 |  | 3.64% |  | 1,968 |  |  | 1,738 |
Finance lease obligations(e) |  |  |  |  | 240 |  |  | 238 |
Unamortized debt premium (discount), net |  |  |  |  | (19) |  |  | (18) |
Unamortized debt issuance expenses |  |  |  |  | (122) |  |  | (117) |
Total long-term debt |  |  |  |  | 16,700 |  |  | 14,910 |
Less: Amount due within one year |  |  |  |  | 502 |  |  | 901 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 16,198 |  |  | $ | 14,009 |
| At December 31, 2023 |  | Balance Outstanding at December 31,
| Maturity |  | Weighted Average Interest Rate |  | 2023 |  | 2022
|  |  |  |  | (in millions)
Mississippi Power |  |  |  |  |  |  |
Senior notes | 2024-2051 |  | 4.27% |  | $ | 1,525 |  |  | $ | 1,425 |
Revenue bonds(c) | 2025-2052 |  | 4.08% |  | 111 |  |  | 111 |
Finance lease obligations(e) |  |  |  |  | 16 |  |  | 17 |
Unamortized debt premium (discount), net |  |  |  |  | 1 |  |  | 2 |
Unamortized debt issuance expenses |  |  |  |  | (9) |  |  | (10) |
Total long-term debt |  |  |  |  | 1,644 |  |  | 1,545 |
Less: Amount due within one year |  |  |  |  | 201 |  |  | 1 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 1,443 |  |  | $ | 1,544 |
Southern Power |  |  |  |  |  |  |
Senior notes(a) | 2025-2046 |  | 4.05% |  | $ | 2,728 |  |  | $ | 2,998 |
Unamortized debt premium (discount), net |  |  |  |  | (4) |  |  | (5) |
Unamortized debt issuance expenses |  |  |  |  | (13) |  |  | (14) |
Total long-term debt |  |  |  |  | 2,711 |  |  | 2,979 |
Less: Amount due within one year |  |  |  |  | — |  |  | 290 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 2,711 |  |  | $ | 2,689 |
Southern Company Gas |  |  |  |  |  |  |
Senior notes | 2025-2051 |  | 4.36% |  | $ | 4,930 |  |  | $ | 4,769 |
First mortgage bonds(d) | 2025-2063 |  | 3.64% |  | 2,500 |  |  | 2,275 |
Medium-term notes | 2026-2027 |  | 7.03% |  | 84 |  |  | 84 |
Other long-term debt | 2024-2045 |  | 3.81% |  | 59 |  |  | 22 |
Unamortized fair value adjustment |  |  |  |  | 302 |  |  | 330 |
Unamortized debt premium (discount), net |  |  |  |  | (8) |  |  | (8) |
Unamortized debt issuance expenses |  |  |  |  | (34) |  |  | (30) |
Total long-term debt |  |  |  |  | 7,833 |  |  | 7,442 |
Less: Amount due within one year |  |  |  |  | — |  |  | 400 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 7,833 |  |  | $ | 7,042 |
(a)Includes a fair value gain (loss) of $(12) million and $(31) million at December 31, 2023 and 2022, respectively, related to Southern Power's foreign currency hedge on its euro-denominated senior notes. (b)Secured by a first priority lien on (i) Georgia Power's undivided ownership interest in Plant Vogtle Units 3 and 4 (primarily the units, the related real property, and any nuclear fuel loaded in the reactor core) and (ii) Georgia Power's rights and obligations under the principal contracts relating to Plant Vogtle Units 3 and 4. See "DOE Loan Guarantee Borrowings" herein for additional information. (c)Revenue bond obligations represent loans to the traditional electric operating companies from public authorities of funds derived from sales by such authorities of revenue bonds issued to finance pollution control and solid waste disposal and wastewater facilities. In some cases, the revenue bond obligations represent obligations under installment sales agreements with respect to facilities constructed with the proceeds of revenue bonds issued by public authorities. The traditional electric operating companies are required to make payments sufficient for the authorities to meet principal and interest requirements of such bonds. Proceeds from certain issuances are restricted until qualifying expenditures are incurred. (d)Secured by substantially all of Nicor Gas' properties. (e)Secured by the underlying lease ROU asset. See Note 9 for additional information.
Schedule of maturities of long-term debt for the next five years | Maturities of long-term debt for the next five years are as follows:
| Southern Company(a) | Alabama Power(b) | Georgia Power(c) | Mississippi Power | Southern Power(d) | Southern Company Gas
| (in millions)
2024 | $ | 2,480 |  | $ | 223 |  | $ | 503 |  | $ | 201 |  | $ | — |  | $ | — |
2025 | 4,124 |  | 251 |  | 849 |  | 12 |  | 500 |  | 300 |
2026 | 3,791 |  | 46 |  | 448 |  | 66 |  | 964 |  | 530 |
2027 | 2,075 |  | 551 |  | 512 |  | 10 |  | — |  | 154 |
2028 | 2,612 |  | 107 |  | 864 |  | 357 |  | — |  | 150 |
(a)See notes (b) and (c) below. (b)Alabama Power's 2024 maturities include $200 million aggregate principal amount of Series 2023A Floating Rate Senior Notes due May 15, 2073 that are repayable at the option of the holders at certain dates beginning in 2024. As a result, the senior notes are classified as securities due within one year on the balance sheets of Southern Company and Alabama Power at December 31, 2023. (c)Amounts include principal amortization related to the FFB borrowings; however, the final maturity date is February 20, 2044. See "DOE Loan Guarantee Borrowings" herein for additional information. (d)Southern Power's 2026 maturities include $564 million of euro-denominated debt at the U.S. dollar denominated hedge settlement amount.
Summary of committed credit arrangements | At December 31, 2023, committed credit arrangements with banks were as follows:
| Expires |  |  |  |  |  |  |
Company | 2024 |  | 2025 |  | 2026 |  | 2028 |  | Total |  | Unused |  |  |  |  |  |  |  | Expires within One Year
| (in millions)
Southern Company parent(a) | $ | 150 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,850 |  |  | $ | 2,000 |  |  | $ | 1,998 |  |  |  |  |  |  |  |  | $ | 150 |
Alabama Power | — |  |  | — |  |  | 650 |  |  | 700 |  |  | 1,350 |  |  | 1,350 |  |  |  |  |  |  |  |  | — |
Georgia Power | — |  |  | — |  |  | — |  |  | 1,750 |  |  | 1,750 |  |  | 1,726 |  |  |  |  |  |  |  |  | — |
Mississippi Power | — |  |  | 125 |  |  | 150 |  |  | — |  |  | 275 |  |  | 275 |  |  |  |  |  |  |  |  | — |
Southern Power(a)(b) | — |  |  | — |  |  | — |  |  | 600 |  |  | 600 |  |  | 589 |  |  |  |  |  |  |  |  | — |
Southern Company Gas(c) | 100 |  |  | — |  |  | — |  |  | 1,500 |  |  | 1,600 |  |  | 1,598 |  |  |  |  |  |  |  |  | 100 |
SEGCO | 30 |  |  | — |  |  | — |  |  | — |  |  | 30 |  |  | 30 |  |  |  |  |  |  |  |  | 30 |
Southern Company | $ | 280 |  |  | $ | 125 |  |  | $ | 800 |  |  | $ | 6,400 |  |  | $ | 7,605 |  |  | $ | 7,566 |  |  |  |  |  |  |  |  | $ | 280 |
(a)Arrangement expiring in 2028 represents a $2.45 billion combined arrangement for Southern Company and Southern Power as borrowers. Pursuant to the combined facility, the allocations between Southern Company and Southern Power may be adjusted. (b)Does not include Southern Power Company's $75 million and $100 million continuing letter of credit facilities for standby letters of credit, expiring in 2025 and 2026, respectively, of which $8 million and $7 million, respectively, was unused at December 31, 2023. Southern Power's subsidiaries are not parties to its bank credit arrangements or letter of credit facilities. (c)Southern Company Gas, as the parent entity, guarantees the obligations of Southern Company Gas Capital, which is the borrower of $800 million of the credit arrangement expiring in 2028. Southern Company Gas' committed credit arrangement expiring in 2028 also includes $700 million for which Nicor Gas is the borrower and which is restricted for working capital needs of Nicor Gas. Pursuant to the multi-year credit arrangement expiring in 2028, the allocations between Southern Company Gas Capital and Nicor Gas may be adjusted. Nicor Gas is also the borrower under a $100 million credit arrangement expiring in 2024. See "Structural Considerations" herein for additional information.
Details of short-term borrowings | Details of short-term borrowings for the applicable Registrants were as follows:
| Notes Payable at December 31, 2023 |  | Notes Payable at December 31, 2022
| Amount Outstanding |  | Weighted Average Interest Rate |  | Amount Outstanding |  | Weighted Average Interest Rate
| (in millions) |  |  |  | (in millions) |  |
Southern Company |  |  |  |  |  |  |
Commercial paper | $ | 1,794 |  |  | 5.6 | % |  | $ | 809 |  |  | 4.7 | %
Short-term bank debt | 520 |  |  | 6.4 | % |  | 1,800 |  |  | 5.0 | %
Total | $ | 2,314 |  |  | 5.7 | % |  | $ | 2,609 |  |  | 4.9 | %
Alabama Power |  |  |  |  |  |  |
Commercial paper | $ | 40 |  |  | 5.5 | % |  | $ | — |  |  | — | %
Georgia Power |  |  |  |  |  |  |
Commercial paper | $ | 809 |  |  | 5.6 | % |  | $ | — |  |  | — | %
Short-term bank debt | 520 |  |  | 6.4 | % |  | 1,600 |  |  | 5.0 | %
Total | $ | 1,329 |  |  | 5.9 | % |  | $ | 1,600 |  |  | 5.0 | %
Southern Power |  |  |  |  |  |  |
Commercial paper | $ | 138 |  |  | 5.5 | % |  | $ | 225 |  |  | 4.7 | %
Southern Company Gas |  |  |  |  |  |  |
Commercial paper: |  |  |  |  |  |  |
Southern Company Gas Capital | $ | 23 |  |  | 5.5 | % |  | $ | 285 |  |  | 4.8 | %
Nicor Gas | 392 |  |  | 5.5 | % |  | 283 |  |  | 4.6 | %
Short-term bank debt: |  |  |  |  |  |  |
Nicor Gas | — |  |  | — | % |  | 200 |  |  | 4.9 | %
Total | $ | 415 |  |  | 5.5 | % |  | $ | 768 |  |  | 4.7 | %
Shares used to compute diluted EPS | Shares used to compute diluted EPS were as follows:
| Average Common Stock Shares
| 2023 |  | 2022 |  | 2021
| (in millions)
As reported shares | 1,092 |  |  | 1,075 |  |  | 1,061 |
Effect of stock-based compensation | 6 |  |  | 6 |  |  | 7 |
Diluted shares | 1,098 |  |  | 1,081 |  |  | 1,068 |
Schedule of preferred stock |
Preferred Stock Redeemed During 2022 | Par Value/Stated Capital Per Share |  | Shares |  | Redemption Price Per Share
4.92% Preferred Stock | $100 |  | 80,000 |  |  | $103.23
4.72% Preferred Stock | $100 |  | 50,000 |  |  | $102.18
4.64% Preferred Stock | $100 |  | 60,000 |  |  | $103.14
4.60% Preferred Stock | $100 |  | 100,000 |  |  | $104.20
4.52% Preferred Stock | $100 |  | 50,000 |  |  | $102.93
4.20% Preferred Stock | $100 |  | 135,115 |  |  | $105.00
5.00% Class A Preferred Stock | $25 |  | 10,000,000 |  |  | $25.00

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