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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables) | 12 Months Ended
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Dec. 31, 2021
Accounting Policies [Abstract] |
Schedule of costs for affiliate transactions | Costs for these services from SCS in 2021, 2020, and 2019 were as follows:
| Alabama Power | Georgia Power | Mississippi Power | Southern Power | Southern Company Gas
| (in millions)
2021 | $ | 504 |  | $ | 663 |  | $ | 120 |  | $ | 89 |  | $ | 239 |
2020 | 478 |  | 639 |  | 149 |  | 87 |  | 237 |
2019 | 527 |  | 704 |  | 118 |  | 90 |  | 183 |
Mississippi Power's and Southern Power's power purchases from affiliates through the Southern Company power pool are included in purchased power on their respective statements of income and were as follows:
| Mississippi Power | Southern Power
| (in millions)
2021 | $ | 9 |  | $ | 15 |
2020 | 4 |  | 8 |
2019 | 3 |  | 14 |
Transportation costs under these agreements in 2021, 2020, and 2019 were as follows:
| Alabama Power | Georgia Power | Southern Power | Southern Company Gas
| (in millions)
2021 | $ | 14 |  | $ | 108 |  | $ | 31 |  | $ | 29 |
2020 | 15 |  | 108 |  | 29 |  | 29 |
2019 | 17 |  | 99 |  | 28 |  | 31 |
The approximate rates for 2021, 2020, and 2019 are as follows:
| 2021 | 2020 | 2019
Alabama Power | 2.7 | % | 2.6 | % | 3.1 | %
Georgia Power | 3.3 | % | 3.0 | % | 2.6 | %
Mississippi Power | 3.6 | % | 3.7 | % | 3.7 | %
Southern Company Gas | 2.8 | % | 2.8 | % | 2.9 | %
Schedule of total AFUDC and interest capitalized | Total AFUDC and interest capitalized for the Registrants in 2021, 2020, and 2019 was as follows:
| Southern Company | Alabama Power | Georgia Power(*) | Mississippi Power | Southern Power | Southern Company Gas
| (in millions)
2021 | $ | 282 |  | $ | 68 |  | $ | 190 |  | $ | — |  | $ | 6 |  | $ | 18 |
2020 | 230 |  | 61 |  | 138 |  | 1 |  | 11 |  | 18 |
2019 | 202 |  | 71 |  | 103 |  | — |  | 15 |  | 13 |
(*)See Note 2 under "Georgia Power – Nuclear Construction" for information on the inclusion of a portion of construction costs related to Plant Vogtle Units 3 and 4 in Georgia Power's rate base.
Schedule of average AFUDC composite rates | The average AFUDC composite rates for 2021, 2020, and 2019 for the traditional electric operating companies and the natural gas distribution utilities were as follows:
| 2021 | 2020 | 2019
Alabama Power | 7.9 | % | 8.1 | % | 8.4 | %
Georgia Power(*) | 7.2 | % | 6.9 | % | 6.9 | %
Mississippi Power | 2.5 | % | 5.4 | % | 7.3 | %
Southern Company Gas: |  |  |
Atlanta Gas Light | 7.7 | % | 7.7 | % | 7.8 | %
Chattanooga Gas | 7.1 | % | 7.1 | % | 7.1 | %
Nicor Gas | 0.1 | % | 0.7 | % | 2.3 | %
(*)Excludes AFUDC related to the construction of Plant Vogtle Units 3 and 4. See Note 2 under "Georgia Power – Nuclear Construction" for additional information.
Schedule of goodwill balances | At December 31, 2021 and 2020, goodwill was as follows:
| Goodwill |
| (in millions)
Southern Company | $ | 5,280 |  |
Southern Company Gas: |  |
Gas distribution operations | $ | 4,034 |  |
Gas marketing services | 981 |  |
Southern Company Gas total | $ | 5,015 |  |
Schedule of intangible assets subject to amortization | At December 31, 2021 and 2020, other intangible assets were as follows:
| At December 31, 2021 |  | At December 31, 2020
| Gross Carrying Amount | Accumulated Amortization | Other Intangible Assets, Net |  | Gross Carrying Amount | Accumulated Amortization | Other Intangible Assets, Net
| (in millions) |  | (in millions)
Southern Company |  |  |  |  |  |  |
Other intangible assets subject to amortization: |  |  |  |  |  |  |
Customer relationships | $ | 212 |  | $ | (150) |  | $ | 62 |  |  | $ | 212 |  | $ | (135) |  | $ | 77 |
Trade names | 64 |  | (38) |  | 26 |  |  | 64 |  | (31) |  | 33 |
Storage and transportation contracts(*) | — |  | — |  | — |  |  | 64 |  | (64) |  | — |
PPA fair value adjustments | 390 |  | (109) |  | 281 |  |  | 390 |  | (89) |  | 301 |
Other | 11 |  | (10) |  | 1 |  |  | 10 |  | (9) |  | 1 |
Total other intangible assets subject to amortization | $ | 677 |  | $ | (307) |  | $ | 370 |  |  | $ | 740 |  | $ | (328) |  | $ | 412 |
Other intangible assets not subject to amortization: |  |  |  |  |  |  |
Federal Communications Commission licenses | 75 |  | — |  | 75 |  |  | 75 |  | — |  | 75 |
Total other intangible assets | $ | 752 |  | $ | (307) |  | $ | 445 |  |  | $ | 815 |  | $ | (328) |  | $ | 487 |
Southern Power |  |  |  |  |  |  |
Other intangible assets subject to amortization: |  |  |  |  |  |  |
PPA fair value adjustments | $ | 390 |  | $ | (109) |  | $ | 281 |  |  | $ | 390 |  | $ | (89) |  | $ | 301 |
Southern Company Gas |  |  |  |  |  |  |
Other intangible assets subject to amortization: |  |  |  |  |  |  |
Gas marketing services |  |  |  |  |  |  |
Customer relationships | $ | 156 |  | $ | (130) |  | $ | 26 |  |  | $ | 156 |  | $ | (119) |  | $ | 37 |
Trade names | 26 |  | (15) |  | 11 |  |  | 26 |  | (12) |  | 14 |
Wholesale gas services |  |  |  |  |  |  |
Storage and transportation contracts(*) | — |  | — |  | — |  |  | 64 |  | (64) |  | — |
Total other intangible assets subject to amortization | $ | 182 |  | $ | (145) |  | $ | 37 |  |  | $ | 246 |  | $ | (195) |  | $ | 51 |
(*)See Note 15 under "Southern Company Gas" for information regarding the sale of Sequent.
Schedule of intangible assets not subject to amortization | At December 31, 2021 and 2020, other intangible assets were as follows:
| At December 31, 2021 |  | At December 31, 2020
| Gross Carrying Amount | Accumulated Amortization | Other Intangible Assets, Net |  | Gross Carrying Amount | Accumulated Amortization | Other Intangible Assets, Net
| (in millions) |  | (in millions)
Southern Company |  |  |  |  |  |  |
Other intangible assets subject to amortization: |  |  |  |  |  |  |
Customer relationships | $ | 212 |  | $ | (150) |  | $ | 62 |  |  | $ | 212 |  | $ | (135) |  | $ | 77 |
Trade names | 64 |  | (38) |  | 26 |  |  | 64 |  | (31) |  | 33 |
Storage and transportation contracts(*) | — |  | — |  | — |  |  | 64 |  | (64) |  | — |
PPA fair value adjustments | 390 |  | (109) |  | 281 |  |  | 390 |  | (89) |  | 301 |
Other | 11 |  | (10) |  | 1 |  |  | 10 |  | (9) |  | 1 |
Total other intangible assets subject to amortization | $ | 677 |  | $ | (307) |  | $ | 370 |  |  | $ | 740 |  | $ | (328) |  | $ | 412 |
Other intangible assets not subject to amortization: |  |  |  |  |  |  |
Federal Communications Commission licenses | 75 |  | — |  | 75 |  |  | 75 |  | — |  | 75 |
Total other intangible assets | $ | 752 |  | $ | (307) |  | $ | 445 |  |  | $ | 815 |  | $ | (328) |  | $ | 487 |
Southern Power |  |  |  |  |  |  |
Other intangible assets subject to amortization: |  |  |  |  |  |  |
PPA fair value adjustments | $ | 390 |  | $ | (109) |  | $ | 281 |  |  | $ | 390 |  | $ | (89) |  | $ | 301 |
Southern Company Gas |  |  |  |  |  |  |
Other intangible assets subject to amortization: |  |  |  |  |  |  |
Gas marketing services |  |  |  |  |  |  |
Customer relationships | $ | 156 |  | $ | (130) |  | $ | 26 |  |  | $ | 156 |  | $ | (119) |  | $ | 37 |
Trade names | 26 |  | (15) |  | 11 |  |  | 26 |  | (12) |  | 14 |
Wholesale gas services |  |  |  |  |  |  |
Storage and transportation contracts(*) | — |  | — |  | — |  |  | 64 |  | (64) |  | — |
Total other intangible assets subject to amortization | $ | 182 |  | $ | (145) |  | $ | 37 |  |  | $ | 246 |  | $ | (195) |  | $ | 51 |
(*)See Note 15 under "Southern Company Gas" for information regarding the sale of Sequent.
Schedule of amortization associated with other intangible assets | Amortization associated with other intangible assets in 2021, 2020, and 2019 was as follows:
| 2021 | 2020 | 2019
| (in millions)
Southern Company(a) | $ | 44 |  | $ | 49 |  | $ | 61 |
Southern Power(b) | 20 |  | 20 |  | 19 |
Southern Company Gas: |  |  |
Gas marketing services | $ | 15 |  | $ | 17 |  | $ | 23 |
Wholesale gas services(b) | — |  | 2 |  | 8 |
Southern Company Gas total | $ | 15 |  | $ | 19 |  | $ | 31 |
(a)Includes $20 million, $22 million, and $27 million in 2021, 2020, and 2019, respectively, recorded as a reduction to operating revenues. (b)Recorded as a reduction to operating revenues.
Schedule of estimated future amortization of other intangible assets | At December 31, 2021, the estimated amortization associated with other intangible assets for the next five years is as follows:
| 2022 | 2023 | 2024 | 2025 | 2026
| (in millions)
Southern Company | $ | 39 |  | $ | 37 |  | $ | 35 |  | $ | 32 |  | $ | 27 |
Southern Power | 20 |  | 20 |  | 20 |  | 20 |  | 20 |
Southern Company Gas | 11 |  | 9 |  | 7 |  | 6 |  | 3 |
Schedule of cash, cash equivalents, and restricted cash | The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets that total to the amount shown in the statements of cash flows for the applicable Registrants:
| Southern Company |  | Southern Power |  | Southern Company Gas
| December 31, 2021 |  | December 31, 2020 |  | December 31, 2021 |  | December 31, 2021 | December 31, 2020
| (in millions) |  | (in millions) |  | (in millions)
Cash and cash equivalents | $ | 1,798 |  |  | $ | 1,065 |  |  | $ | 107 |  |  | $ | 45 |  | $ | 17 |
Restricted cash(a): |  |  |  |  |  |  |  |
Other current assets | 2 |  |  | 2 |  |  | — |  |  | 2 |  | 2 |
Other deferred charges and assets | 29 |  |  | — |  |  | 29 |  |  | — |  | — |
Total cash, cash equivalents, and restricted cash(b) | $ | 1,829 |  |  | $ | 1,068 |  |  | $ | 135 |  |  | $ | 48 |  | $ | 19 |
(a)For Southern Power, reflects restricted cash of $19 million related to tax equity contributions restricted until the Garland battery energy storage facility achieves final contracted capacity and $10 million held to fund estimated construction completion costs at the Deuel Harvest wind facility. See Note 15 under "Southern Power" for additional information. For Southern Company Gas, reflects restricted cash held as collateral for workers' compensation, life insurance, and long-term disability insurance. (b)Total may not add due to rounding.
Reconciliation of restricted cash and cash equivalents | The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets that total to the amount shown in the statements of cash flows for the applicable Registrants:
| Southern Company |  | Southern Power |  | Southern Company Gas
| December 31, 2021 |  | December 31, 2020 |  | December 31, 2021 |  | December 31, 2021 | December 31, 2020
| (in millions) |  | (in millions) |  | (in millions)
Cash and cash equivalents | $ | 1,798 |  |  | $ | 1,065 |  |  | $ | 107 |  |  | $ | 45 |  | $ | 17 |
Restricted cash(a): |  |  |  |  |  |  |  |
Other current assets | 2 |  |  | 2 |  |  | — |  |  | 2 |  | 2 |
Other deferred charges and assets | 29 |  |  | — |  |  | 29 |  |  | — |  | — |
Total cash, cash equivalents, and restricted cash(b) | $ | 1,829 |  |  | $ | 1,068 |  |  | $ | 135 |  |  | $ | 48 |  | $ | 19 |
(a)For Southern Power, reflects restricted cash of $19 million related to tax equity contributions restricted until the Garland battery energy storage facility achieves final contracted capacity and $10 million held to fund estimated construction completion costs at the Deuel Harvest wind facility. See Note 15 under "Southern Power" for additional information. For Southern Company Gas, reflects restricted cash held as collateral for workers' compensation, life insurance, and long-term disability insurance. (b)Total may not add due to rounding.
Schedule of storm damage reserves | In accordance with their respective state PSC orders, the traditional electric operating companies accrued the following amounts related to storm damage recovery in 2021, 2020, and 2019:
| Southern Company(a)(b) | Alabama Power(a) | Georgia Power | Mississippi Power(b)
| (in millions)
2021 | $ | 286 |  | $ | 75 |  | $ | 213 |  | $ | (2) |
2020 | 326 |  | 112 |  | 213 |  | 1 |
2019 | 170 |  | 139 |  | 30 |  | 1 |
(a)Includes $39 million applied in 2019 to Alabama Power's NDR from its remaining excess deferred income tax regulatory liability balance in accordance with an Alabama PSC order. (b)Mississippi Power's net accrual includes carrying costs, as well as amortization of related excess deferred income tax benefits.
Schedule of AOCI (loss) balances, net of tax effects | AOCI (loss) balances, net of tax effects, for Southern Company, Southern Power, and Southern Company Gas were as follows:
| Qualifying Hedges |  | Pension and Other Postretirement Benefit Plans |  | Accumulated Other Comprehensive Income (Loss)(*)
| (in millions)
Southern Company |  |  |  |  |
Balance at December 31, 2020 | $ | (209) |  |  | $ | (187) |  |  | $ | (395) |
Current period change | 47 |  |  | 111 |  |  | 158 |
Balance at December 31, 2021 | $ | (162) |  |  | $ | (76) |  |  | $ | (237) |
Southern Power |  |  |  |  |
Balance at December 31, 2020 | $ | (21) |  |  | $ | (47) |  |  | $ | (67) |
Current period change | 22 |  |  | 18 |  |  | 40 |
Balance at December 31, 2021 | $ | 1 |  |  | $ | (29) |  |  | $ | (27) |
Southern Company Gas |  |  |  |  |
Balance at December 31, 2020 | $ | (20) |  |  | $ | (2) |  |  | $ | (22) |
Current period change | 6 |  |  | 40 |  |  | 46 |
Balance at December 31, 2021 | $ | (14) |  |  | $ | 38 |  |  | $ | 24 |
(*)May not add due to rounding.

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