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FINANCING (Tables) | 12 Months Ended
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Dec. 31, 2021
Debt Disclosure [Abstract] |
Summary of long-term debt | Details of long-term debt at December 31, 2021 and 2020 are provided in the following table:
| At December 31, 2021 |  | Balance Outstanding at December 31,
| Maturity |  | Weighted Average Interest Rate |  | 2021 |  | 2020
|  |  |  |  | (in millions)
Southern Company |  |  |  |  |  |  |
Senior notes(a) | 2022-2052 |  | 3.62% |  | $ | 33,120 |  |  | $ | 30,850 |
Junior subordinated notes | 2024-2081 |  | 4.00% |  | 8,918 |  |  | 7,295 |
FFB loans(b) | 2022-2044 |  | 2.88% |  | 4,962 |  |  | 4,618 |
Pollution control revenue bonds(c) | 2022-2053 |  | 1.05% |  | 2,662 |  |  | 2,675 |
First mortgage bonds(d) | 2023-2060 |  | 3.53% |  | 2,100 |  |  | 1,900 |
Medium-term notes | 2022-2027 |  | 7.60% |  | 130 |  |  | 160 |
Other long-term debt | 2022-2026 |  | 0.79% |  | 270 |  |  | 370 |
Other revenue bonds |  |  |  |  | — |  |  | 320 |
Debt payable to affiliated trusts(e) |  |  |  |  | — |  |  | 206 |
Finance lease obligations(f) |  |  |  |  | 215 |  |  | 231 |
Unamortized fair value adjustment |  |  |  |  | 359 |  |  | 393 |
Unamortized debt premium (discount), net |  |  |  |  | (216) |  |  | (201) |
Unamortized debt issuance expenses |  |  |  |  | (243) |  |  | (237) |
Total long-term debt |  |  |  |  | 52,277 |  |  | 48,580 |
Less: Amount due within one year |  |  |  |  | 2,157 |  |  | 3,507 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 50,120 |  |  | $ | 45,073 |
Alabama Power |  |  |  |  |  |  |
Senior notes | 2022-2052 |  | 3.89% |  | $ | 8,725 |  |  | $ | 7,625 |
Pollution control revenue bonds(c) | 2024-2038 |  | 0.55% |  | 995 |  |  | 1,060 |
Other long-term debt | 2026 |  | 1.24% |  | 45 |  |  | 45 |
Debt payable to affiliated trusts(e) |  |  |  |  | — |  |  | 206 |
Finance lease obligations(f) |  |  |  |  | 4 |  |  | 5 |
Unamortized debt premium (discount), net |  |  |  |  | (18) |  |  | (16) |
Unamortized debt issuance expenses |  |  |  |  | (64) |  |  | (56) |
Total long-term debt |  |  |  |  | 9,687 |  |  | 8,869 |
Less: Amount due within one year |  |  |  |  | 751 |  |  | 311 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 8,936 |  |  | $ | 8,558 |
Georgia Power |  |  |  |  |  |  |
Senior notes | 2022-2051 |  | 3.61% |  | $ | 6,825 |  |  | $ | 6,400 |
Junior subordinated notes | 2077 |  | 5.00% |  | 270 |  |  | 270 |
FFB loans(b) | 2022-2044 |  | 2.88% |  | 4,962 |  |  | 4,618 |
Pollution control revenue bonds(c) | 2022-2053 |  | 1.33% |  | 1,591 |  |  | 1,538 |
Other long-term debt | 2022 |  | 0.70% |  | 125 |  |  | 125 |
Finance lease obligations(f) |  |  |  |  | 136 |  |  | 145 |
Unamortized debt premium (discount), net |  |  |  |  | (11) |  |  | (12) |
Unamortized debt issuance expenses |  |  |  |  | (114) |  |  | (114) |
Total long-term debt |  |  |  |  | 13,784 |  |  | 12,970 |
Less: Amount due within one year |  |  |  |  | 675 |  |  | 542 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 13,109 |  |  | $ | 12,428 |
| At December 31, 2021 |  | Balance Outstanding at December 31,
| Maturity |  | Weighted Average Interest Rate |  | 2021 |  | 2020
|  |  |  |  | (in millions)
Mississippi Power |  |  |  |  |  |  |
Senior notes | 2024-2051 |  | 3.43% |  | $ | 1,425 |  |  | $ | 900 |
Pollution control revenue bonds(c) | 2025-2028 |  | 1.86% |  | 76 |  |  | 76 |
Other revenue bonds |  |  |  |  | — |  |  | 320 |
Other long-term debt |  |  |  |  | — |  |  | 100 |
Finance lease obligations(f) |  |  |  |  | 18 |  |  | 19 |
Unamortized debt premium (discount), net |  |  |  |  | 2 |  |  | 11 |
Unamortized debt issuance expenses |  |  |  |  | (10) |  |  | (7) |
Total long-term debt |  |  |  |  | 1,511 |  |  | 1,419 |
Less: Amount due within one year |  |  |  |  | 1 |  |  | 406 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 1,510 |  |  | $ | 1,013 |
Southern Power |  |  |  |  |  |  |
Senior notes(a) | 2022-2046 |  | 3.74% |  | $ | 3,711 |  |  | $ | 3,714 |
Unamortized debt premium (discount), net |  |  |  |  | (6) |  |  | (6) |
Unamortized debt issuance expenses |  |  |  |  | (17) |  |  | (16) |
Total long-term debt |  |  |  |  | 3,688 |  |  | 3,692 |
Less: Amount due within one year |  |  |  |  | 679 |  |  | 299 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 3,009 |  |  | $ | 3,393 |
Southern Company Gas |  |  |  |  |  |  |
Senior notes | 2023-2051 |  | 3.96% |  | $ | 4,348 |  |  | $ | 4,200 |
First mortgage bonds(d) | 2023-2060 |  | 3.53% |  | 2,100 |  |  | 1,900 |
Medium-term notes | 2022-2027 |  | 7.60% |  | 130 |  |  | 160 |
Unamortized fair value adjustment |  |  |  |  | 359 |  |  | 393 |
Unamortized debt premium (discount), net |  |  |  |  | (35) |  |  | (27) |
Total long-term debt |  |  |  |  | 6,902 |  |  | 6,626 |
Less: Amount due within one year |  |  |  |  | 47 |  |  | 333 |
Total long-term debt excluding amount due within one year |  |  |  |  | $ | 6,855 |  |  | $ | 6,293 |
(a)Includes a fair value gain (loss) of $5 million and $109 million at December 31, 2021 and 2020, respectively, related to Southern Power's foreign currency hedge on its €1.1 billion 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 under construction, 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)Pollution control 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 facilities. In some cases, the pollution control 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)At December 31, 2020, Alabama Power had a wholly-owned trust subsidiary for the purpose of issuing preferred securities. The proceeds of the related equity investments and preferred security sales were loaned back to Alabama Power through the issuance of junior subordinated notes, which Alabama Power redeemed during 2021. The junior subordinated notes constituted substantially all of the assets of this trust. Alabama Power considered the mechanisms and obligations relating to the preferred securities issued for its benefit, taken together, constituted a full and unconditional guarantee by it of the trust's payment obligations with respect to these securities. See Note 1 under "Variable Interest Entities" for additional information on the accounting treatment for this trust and the related securities. (f)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 | Georgia Power(b) | Mississippi Power | Southern Power(c) | Southern Company Gas
| (in millions)
2022 | $ | 2,157 |  | $ | 751 |  | $ | 676 |  | $ | 1 |  | $ | 677 |  | $ | 46 |
2023 | 3,738 |  | 301 |  | 897 |  | 1 |  | 290 |  | 400 |
2024 | 2,280 |  | 22 |  | 498 |  | 201 |  | — |  | — |
2025 | 1,199 |  | 250 |  | 145 |  | 11 |  | 500 |  | 300 |
2026 | 3,723 |  | 45 |  | 441 |  | 1 |  | 964 |  | 530 |
(a)Amount for 2022 excludes junior subordinated notes totaling $1.725 billion at the parent entity that Southern Company has agreed to remarket in 2022 in connection with the related stock purchase contracts; however, the final maturity dates are in 2024 and 2027 (one half in each year). See "Equity Units" herein for additional information. Also see notes (b) and (c) below. (b)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. (c)Southern Power's 2022 maturity and $564 million of its 2026 maturities represent euro-denominated debt at the U.S. dollar denominated hedge settlement amount.
Summary of committed credit arrangements | At December 31, 2021, committed credit arrangements with banks were as follows:
| Expires |  |  |  |  |  |  |
Company | 2022 |  | 2023 |  | 2024 |  | 2026 |  | Total |  | Unused |  |  |  |  |  |  |  | Due within One Year
| (in millions)
Southern Company parent | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 2,000 |  |  | $ | 2,000 |  |  | $ | 1,998 |  |  |  |  |  |  |  |  | $ | — |
Alabama Power | — |  |  | — |  |  | 550 |  |  | 700 |  |  | 1,250 |  |  | 1,250 |  |  |  |  |  |  |  |  | — |
Georgia Power | — |  |  | — |  |  | — |  |  | 1,750 |  |  | 1,750 |  |  | 1,726 |  |  |  |  |  |  |  |  | — |
Mississippi Power | — |  |  | 125 |  |  | 150 |  |  | — |  |  | 275 |  |  | 275 |  |  |  |  |  |  |  |  | — |
Southern Power(a) | — |  |  | — |  |  | — |  |  | 600 |  |  | 600 |  |  | 568 |  |  |  |  |  |  |  |  | — |
Southern Company Gas(b) | 250 |  |  | — |  |  | — |  |  | 1,500 |  |  | 1,750 |  |  | 1,747 |  |  |  |  |  |  |  |  | 250 |
SEGCO | 30 |  |  | — |  |  | — |  |  | — |  |  | 30 |  |  | 30 |  |  |  |  |  |  |  |  | 30 |
Southern Company | $ | 280 |  |  | $ | 125 |  |  | $ | 700 |  |  | $ | 6,550 |  |  | $ | 7,655 |  |  | $ | 7,594 |  |  |  |  |  |  |  |  | $ | 280 |
(a)Does not include Southern Power Company's $75 million and $60 million continuing letter of credit facilities for standby letters of credit expiring in 2023, of which $8 million and $4 million, respectively, was unused at December 31, 2021. Subsequent to December 31, 2021, Southern Power amended its $60 million letter of credit facility, which, among other things, extended the expiration date from 2023 to 2025 and increased the amount to $75 million. Southern Power's subsidiaries are not parties to its bank credit arrangements or letter of credit facilities. (b)Southern Company Gas, as the parent entity, guarantees the obligations of Southern Company Gas Capital, which is the borrower of $800 million of the arrangement expiring in 2026 and all $250 million of the arrangement expiring in 2022. Southern Company Gas' committed credit arrangement expiring in 2026 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 2026, the allocations between Southern Company Gas Capital and Nicor Gas may be adjusted. 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, 2021 |  | Notes Payable at December 31, 2020
| Amount Outstanding |  | Weighted Average Interest Rate |  | Amount Outstanding |  | Weighted Average Interest Rate
| (in millions) |  |  |  | (in millions) |  |
Southern Company |  |  |  |  |  |  |
Commercial paper | $ | 1,140 |  |  | 0.3 | % |  | $ | 609 |  |  | 0.3 | %
Short-term bank debt | 300 |  |  | 0.7 | % |  | — |  |  | — | %
Total | $ | 1,440 |  |  | 0.4 | % |  | $ | 609 |  |  | 0.3 | %
Georgia Power |  |  |  |  |  |  |
Commercial paper | $ | — |  |  | — | % |  | $ | 60 |  |  | 0.3 | %
Mississippi Power |  |  |  |  |  |  |
Commercial paper | $ | — |  |  | — | % |  | $ | 25 |  |  | 0.4 | %
Southern Power |  |  |  |  |  |  |
Commercial paper | $ | 211 |  |  | 0.3 | % |  | $ | 175 |  |  | 0.3 | %
Southern Company Gas |  |  |  |  |  |  |
Commercial paper: |  |  |  |  |  |  |
Southern Company Gas Capital | $ | 379 |  |  | 0.3 | % |  | $ | 220 |  |  | 0.3 | %
Nicor Gas | 530 |  |  | 0.3 | % |  | 104 |  |  | 0.2 | %
Short-term bank debt: |  |  |  |  |  |  |
Nicor Gas | 300 |  |  | 0.7 | % |  | — |  |  | — | %
Total | $ | 1,209 |  |  | 0.4 | % |  | $ | 324 |  |  | 0.2 | %
Shares used to compute diluted EPS | Shares used to compute diluted EPS were as follows:
| Average Common Stock Shares
| 2021 |  | 2020 |  | 2019
| (in millions)
As reported shares | 1,061 |  |  | 1,058 |  |  | 1,046 |
Effect of stock-based compensation | 7 |  |  | 7 |  |  | 8 |
Diluted shares | 1,068 |  |  | 1,065 |  |  | 1,054 |
Schedule of preferred stock | Information for each outstanding series is in the table below:
Preferred Stock | Par Value/Stated Capital Per Share |  | Shares Outstanding |  | 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(*)
(*)$25.50 if prior to October 1, 2022

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