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ASSET RETIREMENT OBLIGATIONS (Tables) | 12 Months Ended
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Dec. 31, 2023
Asset Retirement Obligation Disclosure [Abstract] |
Details of AROs included in the balance sheets | Details of the AROs included in the balance sheets are as follows:
| Southern Company | Alabama Power | Georgia Power | Mississippi Power | Southern Power(*)
| (in millions)
Balance at December 31, 2021 | $ | 11,687 |  | $ | 4,334 |  | $ | 6,824 |  | $ | 190 |  | $ | 131 |
Liabilities incurred | 36 |  | — |  | 35 |  | — |  | — |
Liabilities settled | (455) |  | (205) |  | (212) |  | (20) |  | — |
Accretion expense | 406 |  | 158 |  | 231 |  | 6 |  | 6 |
Cash flow revisions | (834) |  | — |  | (844) |  | 3 |  | 7 |
Balance at December 31, 2022 | $ | 10,840 |  | $ | 4,287 |  | $ | 6,034 |  | $ | 179 |  | $ | 144 |
Liabilities incurred | 90 |  | — |  | 90 |  | — |  | — |
Liabilities settled | (617) |  | (270) |  | (304) |  | (18) |  | — |
Accretion expense | 403 |  | 156 |  | 230 |  | 5 |  | 6 |
Cash flow revisions | (399) |  | (15) |  | (385) |  | 2 |  | — |
Balance at December 31, 2023 | $ | 10,317 |  | $ | 4,158 |  | $ | 5,665 |  | $ | 168 |  | $ | 150 |
(*)Included in other deferred credits and liabilities on Southern Power's consolidated balance sheets.
Investment securities in the Funds | Investment securities in the Funds for December 31, 2023 and 2022 were as follows:
| Southern Company | Alabama Power | Georgia Power
| (in millions)
At December 31, 2023: |  |  |
Equity securities | $ | 1,288 |  | $ | 796 |  | $ | 492 |
Debt securities | 895 |  | 277 |  | 618 |
Other securities | 239 |  | 186 |  | 53 |
Total investment securities in the Funds | $ | 2,422 |  | $ | 1,259 |  | $ | 1,163 |
At December 31, 2022: |  |  |
Equity securities | $ | 1,095 |  | $ | 690 |  | $ | 405 |
Debt securities | 838 |  | 267 |  | 571 |
Other securities | 210 |  | 168 |  | 42 |
Total investment securities in the Funds(*) | $ | 2,143 |  | $ | 1,125 |  | $ | 1,018 |
(*)For Southern Company and Georgia Power, these amounts include investment securities pledged to creditors and collateral received and excludes payables related to a securities lending program Georgia Power's Funds previously participated in through the managers of the Funds. Under this program, Georgia Power's Funds' investment securities were loaned to institutional investors for a fee. Securities loaned were fully collateralized by cash, letters of credit, and/or securities issued or guaranteed by the U.S. government or its agencies or instrumentalities. At December 31, 2022, approximately $35 million of the fair market value of Georgia Power's Funds' securities were on loan and pledged to creditors under the Funds' managers' securities lending program. At December 31, 2022, the fair value of the collateral received was approximately $36 million and could only be sold by the borrower upon the return of the loaned securities. The collateral received was treated as a non-cash item in the statements of cash flows.
Fair value increases (decreases) of the Funds | The fair value increases (decreases) of the Funds, including unrealized gains (losses) and reinvested interest and dividends and excluding the Funds' expenses, for 2023, 2022, and 2021 are shown in the table below.
| Southern Company | Alabama Power | Georgia Power
| (in millions)
Fair value increases (decreases) |  |  |
2023 | $ | 281 |  | $ | 157 |  | $ | 124 |
2022 | (360) |  | (171) |  | (189) |
2021 | 274 |  | 200 |  | 74 |
Unrealized gains (losses) |  |  |
At December 31, 2023 | $ | 241 |  | $ | 119 |  | $ | 122 |
At December 31, 2022 | (391) |  | (204) |  | (187) |
At December 31, 2021 | (27) |  | (30) |  | 3 |
At December 31, 2023, assets and liabilities measured at fair value on a recurring basis during the period, together with their associated level of the fair value hierarchy, were as follows:
| Fair Value Measurements Using |  |
| Quoted Prices in Active Markets for Identical Assets |  | Significant Other Observable Inputs |  | Significant Unobservable Inputs |  | Net Asset Value as a Practical Expedient |  |
At December 31, 2023: | (Level 1) |  | (Level 2) |  | (Level 3) |  | (NAV) |  | Total
| (in millions)
Southern Company |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a) | $ | 6 |  |  | $ | 49 |  |  | $ | — |  |  | $ | — |  |  | $ | 55 |
Investments in trusts:(b) |  |  |  |  |  |  |  |  |
Domestic equity | 764 |  |  | 216 |  |  | — |  |  | — |  |  | 980 |
Foreign equity | 145 |  |  | 171 |  |  | — |  |  | — |  |  | 316 |
U.S. Treasury and government agency securities | — |  |  | 369 |  |  | — |  |  | — |  |  | 369 |
Municipal bonds | — |  |  | 48 |  |  | — |  |  | — |  |  | 48 |
Pooled funds – fixed income | — |  |  | 6 |  |  | — |  |  | — |  |  | 6 |
Corporate bonds | — |  |  | 389 |  |  | — |  |  | — |  |  | 389 |
Mortgage and asset backed securities | — |  |  | 89 |  |  | — |  |  | — |  |  | 89 |
Private equity | — |  |  | — |  |  | — |  |  | 169 |  |  | 169 |
Cash and cash equivalents | 3 |  |  | — |  |  | — |  |  | — |  |  | 3 |
Other | 58 |  |  | 3 |  |  | — |  |  | 9 |  |  | 70 |
Cash equivalents and restricted cash | 253 |  |  | 15 |  |  | — |  |  | — |  |  | 268 |
Other investments | 9 |  |  | 27 |  |  | 8 |  |  | — |  |  | 44 |
Total | $ | 1,238 |  |  | $ | 1,382 |  |  | $ | 8 |  |  | $ | 178 |  |  | $ | 2,806 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a) | $ | 46 |  |  | $ | 312 |  |  | $ | — |  |  | $ | — |  |  | $ | 358 |
Interest rate derivatives | — |  |  | 264 |  |  | — |  |  | — |  |  | 264 |
Foreign currency derivatives | — |  |  | 122 |  |  | — |  |  | — |  |  | 122 |
Contingent consideration | 3 |  |  | — |  |  | 16 |  |  | — |  |  | 19 |
Other | — |  |  | 13 |  |  | — |  |  | — |  |  | 13 |
Total | $ | 49 |  |  | $ | 711 |  |  | $ | 16 |  |  | $ | — |  |  | $ | 776 |
| Fair Value Measurements Using |  |
| Quoted Prices in Active Markets for Identical Assets |  | Significant Other Observable Inputs |  | Significant Unobservable Inputs |  | Net Asset Value as a Practical Expedient |  |
At December 31, 2023: | (Level 1) |  | (Level 2) |  | (Level 3) |  | (NAV) |  | Total
| (in millions)
Alabama Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 15 |
Nuclear decommissioning trusts:(b) |  |  |  |  |  |  |  |  |
Domestic equity | 443 |  |  | 208 |  |  | — |  |  | — |  |  | 651 |
Foreign equity | 145 |  |  | — |  |  | — |  |  | — |  |  | 145 |
U.S. Treasury and government agency securities | — |  |  | 20 |  |  | — |  |  | — |  |  | 20 |
Municipal bonds | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
Corporate bonds | — |  |  | 231 |  |  | — |  |  | — |  |  | 231 |
Mortgage and asset backed securities | — |  |  | 25 |  |  | — |  |  | — |  |  | 25 |
Private equity | — |  |  | — |  |  | — |  |  | 169 |  |  | 169 |
Other | 8 |  |  | — |  |  | — |  |  | 9 |  |  | 17 |
Cash equivalents and restricted cash | 119 |  |  | 15 |  |  | — |  |  | — |  |  | 134 |
Other investments | — |  |  | 27 |  |  | — |  |  | — |  |  | 27 |
Total | $ | 715 |  |  | $ | 542 |  |  | $ | — |  |  | $ | 178 |  |  | $ | 1,435 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 110 |  |  | $ | — |  |  | $ | — |  |  | $ | 110 |
Georgia Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 13 |  |  | $ | — |  |  | $ | — |  |  | $ | 13 |
Nuclear decommissioning trusts:(b) |  |  |  |  |  |  |  |  |
Domestic equity | 321 |  |  | 1 |  |  | — |  |  | — |  |  | 322 |
Foreign equity | — |  |  | 170 |  |  | — |  |  | — |  |  | 170 |
U.S. Treasury and government agency securities | — |  |  | 349 |  |  | — |  |  | — |  |  | 349 |
Municipal bonds | — |  |  | 47 |  |  | — |  |  | — |  |  | 47 |
Corporate bonds | — |  |  | 158 |  |  | — |  |  | — |  |  | 158 |
Mortgage and asset backed securities | — |  |  | 64 |  |  | — |  |  | — |  |  | 64 |
Other | 50 |  |  | 3 |  |  | — |  |  | — |  |  | 53 |
Total | $ | 371 |  |  | $ | 805 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,176 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 124 |  |  | $ | — |  |  | $ | — |  |  | $ | 124 |
| Fair Value Measurements Using |  |
| Quoted Prices in Active Markets for Identical Assets |  | Significant Other Observable Inputs |  | Significant Unobservable Inputs |  | Net Asset Value as a Practical Expedient |  |
At December 31, 2023: | (Level 1) |  | (Level 2) |  | (Level 3) |  | (NAV) |  | Total
| (in millions)
Mississippi Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 15 |
Cash equivalents | 17 |  |  | — |  |  | — |  |  | — |  |  | 17 |
Total | $ | 17 |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 32 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 61 |  |  | $ | — |  |  | $ | — |  |  | $ | 61 |
Southern Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | 3 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 5 |  |  | $ | — |  |  | $ | — |  |  | $ | 5 |
Foreign currency derivatives | — |  |  | 22 |  |  | — |  |  | — |  |  | 22 |
Contingent consideration | 3 |  |  | — |  |  | 16 |  |  | — |  |  | 19 |
Other | — |  |  | 13 |  |  | — |  |  | — |  |  | 13 |
Total | $ | 3 |  |  | $ | 40 |  |  | $ | 16 |  |  | $ | — |  |  | $ | 59 |
Southern Company Gas |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a) | $ | 6 |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | 9 |
Non-qualified deferred compensation trusts: |  |  |  |  |  |  |  |  |
Domestic equity | — |  |  | 7 |  |  | — |  |  | — |  |  | 7 |
Foreign equity | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
Pooled funds - fixed income | — |  |  | 6 |  |  | — |  |  | — |  |  | 6 |
Cash and cash equivalents | 3 |  |  | — |  |  | — |  |  | — |  |  | 3 |
Total | $ | 9 |  |  | $ | 17 |  |  | $ | — |  |  | $ | — |  |  | $ | 26 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a)(b) | $ | 46 |  |  | $ | 12 |  |  | $ | — |  |  | $ | — |  |  | $ | 58 |
Interest rate derivatives | — |  |  | 79 |  |  | — |  |  | — |  |  | 79 |
Total | $ | 46 |  |  | $ | 91 |  |  | $ | — |  |  | $ | — |  |  | $ | 137 |
(a)Excludes cash collateral of $62 million. (b)Excludes receivables related to investment income, pending investment sales, payables related to pending investment purchases, and currencies. See Note 6 under "Nuclear Decommissioning" for additional information. At December 31, 2022, assets and liabilities measured at fair value on a recurring basis during the period, together with their associated level of the fair value hierarchy, were as follows:
| Fair Value Measurements Using |  |
| Quoted Prices in Active Markets for Identical Assets |  | Significant Other Observable Inputs |  | Significant Unobservable Inputs |  | Net Asset Value as a Practical Expedient |  |
At December 31, 2022: | (Level 1) |  | (Level 2) |  | (Level 3) |  | (NAV) |  | Total
| (in millions)
Southern Company |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a) | $ | 18 |  |  | $ | 181 |  |  | $ | — |  |  | $ | — |  |  | $ | 199 |
Interest rate derivatives | — |  |  | 12 |  |  | — |  |  | — |  |  | 12 |
Investments in trusts:(b)(c) |  |  |  |  |  |  |  |  |
Domestic equity | 651 |  |  | 178 |  |  | — |  |  | — |  |  | 829 |
Foreign equity | 125 |  |  | 150 |  |  | — |  |  | — |  |  | 275 |
U.S. Treasury and government agency securities | — |  |  | 285 |  |  | — |  |  | — |  |  | 285 |
Municipal bonds | — |  |  | 51 |  |  | — |  |  | — |  |  | 51 |
Pooled funds – fixed income | — |  |  | 7 |  |  | — |  |  | — |  |  | 7 |
Corporate bonds | — |  |  | 412 |  |  | — |  |  | — |  |  | 412 |
Mortgage and asset backed securities | — |  |  | 90 |  |  | — |  |  | — |  |  | 90 |
Private equity | — |  |  | — |  |  | — |  |  | 161 |  |  | 161 |
Cash and cash equivalents | 4 |  |  | — |  |  | — |  |  | — |  |  | 4 |
Other | 37 |  |  | 12 |  |  | — |  |  | — |  |  | 49 |
Cash equivalents | 1,427 |  |  | 20 |  |  | — |  |  | — |  |  | 1,447 |
Other investments | 9 |  |  | 26 |  |  | — |  |  | — |  |  | 35 |
Total | $ | 2,271 |  |  | $ | 1,424 |  |  | $ | — |  |  | $ | 161 |  |  | $ | 3,856 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a) | $ | 32 |  |  | $ | 178 |  |  | $ | — |  |  | $ | — |  |  | $ | 210 |
Interest rate derivatives | — |  |  | 302 |  |  | — |  |  | — |  |  | 302 |
Foreign currency derivatives | — |  |  | 216 |  |  | — |  |  | — |  |  | 216 |
Contingent consideration | — |  |  | — |  |  | 12 |  |  | — |  |  | 12 |
Other | — |  |  | 13 |  |  | — |  |  | — |  |  | 13 |
Total | $ | 32 |  |  | $ | 709 |  |  | $ | 12 |  |  | $ | — |  |  | $ | 753 |
| Fair Value Measurements Using |  |
| Quoted Prices in Active Markets for Identical Assets |  | Significant Other Observable Inputs |  | Significant Unobservable Inputs |  | Net Asset Value as a Practical Expedient |  |
At December 31, 2022: | (Level 1) |  | (Level 2) |  | (Level 3) |  | (NAV) |  | Total
| (in millions)
Alabama Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 62 |  |  | $ | — |  |  | $ | — |  |  | $ | 62 |
Nuclear decommissioning trusts:(b) |  |  |  |  |  |  |  |  |
Domestic equity | 396 |  |  | 169 |  |  | — |  |  | — |  |  | 565 |
Foreign equity | 125 |  |  | — |  |  | — |  |  | — |  |  | 125 |
U.S. Treasury and government agency securities | — |  |  | 19 |  |  | — |  |  | — |  |  | 19 |
Municipal bonds | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
Corporate bonds | — |  |  | 225 |  |  | — |  |  | — |  |  | 225 |
Mortgage and asset backed securities | — |  |  | 22 |  |  | — |  |  | — |  |  | 22 |
Private equity | — |  |  | — |  |  | — |  |  | 161 |  |  | 161 |
Other | 7 |  |  | — |  |  | — |  |  | — |  |  | 7 |
Cash equivalents | 438 |  |  | 20 |  |  | — |  |  | — |  |  | 458 |
Other investments | — |  |  | 26 |  |  | — |  |  | — |  |  | 26 |
Total | $ | 966 |  |  | $ | 544 |  |  | $ | — |  |  | $ | 161 |  |  | $ | 1,671 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 39 |  |  | $ | — |  |  | $ | — |  |  | $ | 39 |
Georgia Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 42 |  |  | $ | — |  |  | $ | — |  |  | $ | 42 |
Nuclear decommissioning trusts:(b)(c) |  |  |  |  |  |  |  |  |
Domestic equity | 255 |  |  | 1 |  |  | — |  |  | — |  |  | 256 |
Foreign equity | — |  |  | 149 |  |  | — |  |  | — |  |  | 149 |
U.S. Treasury and government agency securities | — |  |  | 266 |  |  | — |  |  | — |  |  | 266 |
Municipal bonds | — |  |  | 50 |  |  | — |  |  | — |  |  | 50 |
Corporate bonds | — |  |  | 187 |  |  | — |  |  | — |  |  | 187 |
Mortgage and asset backed securities | — |  |  | 68 |  |  | — |  |  | — |  |  | 68 |
Other | 30 |  |  | 12 |  |  | — |  |  | — |  |  | 42 |
Cash equivalents | 355 |  |  | — |  |  | — |  |  | — |  |  | 355 |
Total | $ | 640 |  |  | $ | 775 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,415 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 62 |  |  | $ | — |  |  | $ | — |  |  | $ | 62 |
| Fair Value Measurements Using |  |
| Quoted Prices in Active Markets for Identical Assets |  | Significant Other Observable Inputs |  | Significant Unobservable Inputs |  | Net Asset Value as a Practical Expedient |  |
At December 31, 2022: | (Level 1) |  | (Level 2) |  | (Level 3) |  | (NAV) |  | Total
| (in millions)
Mississippi Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 59 |  |  | $ | — |  |  | $ | — |  |  | $ | 59 |
Cash equivalents | 47 |  |  | — |  |  | — |  |  | — |  |  | 47 |
Total | $ | 47 |  |  | $ | 59 |  |  | $ | — |  |  | $ | — |  |  | $ | 106 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 32 |  |  | $ | — |  |  | $ | — |  |  | $ | 32 |
Southern Power |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 8 |  |  | $ | — |  |  | $ | — |  |  | $ | 8 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives | $ | — |  |  | $ | 12 |  |  | $ | — |  |  | $ | — |  |  | $ | 12 |
Foreign currency derivatives | — |  |  | 47 |  |  | — |  |  | — |  |  | 47 |
Contingent consideration | — |  |  | — |  |  | 12 |  |  | — |  |  | 12 |
Other | — |  |  | 13 |  |  | — |  |  | — |  |  | 13 |
Total | $ | — |  |  | $ | 72 |  |  | $ | 12 |  |  | $ | — |  |  | $ | 84 |
Southern Company Gas |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a) | $ | 18 |  |  | $ | 10 |  |  | $ | — |  |  | $ | — |  |  | $ | 28 |
Non-qualified deferred compensation trusts: |  |  |  |  |  |  |  |  |
Domestic equity | — |  |  | 8 |  |  | — |  |  | — |  |  | 8 |
Foreign equity | — |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
Pooled funds - fixed income | — |  |  | 7 |  |  | — |  |  | — |  |  | 7 |
Cash equivalents | 4 |  |  | — |  |  | — |  |  | — |  |  | 4 |
Cash equivalents | 50 |  |  | — |  |  | — |  |  | — |  |  | 50 |
Total | $ | 72 |  |  | $ | 26 |  |  | $ | — |  |  | $ | — |  |  | $ | 98 |
Liabilities: |  |  |  |  |  |  |  |  |
Energy-related derivatives(a)(b) | $ | 32 |  |  | $ | 33 |  |  | $ | — |  |  | $ | — |  |  | $ | 65 |
Interest rate derivatives | — |  |  | 86 |  |  | — |  |  | — |  |  | 86 |
Total | $ | 32 |  |  | $ | 119 |  |  | $ | — |  |  | $ | — |  |  | $ | 151 |
(a)Excludes cash collateral of $41 million. (b)Excludes receivables related to investment income, pending investment sales, payables related to pending investment purchases, and currencies. See Note 6 under "Nuclear Decommissioning" for additional information. (c)Includes investment securities pledged to creditors and collateral received and excludes payables related to the securities lending program. See Note 6 under "Nuclear Decommissioning" for additional information.
Accumulated provisions for the external decommissioning trust funds | At December 31, 2023 and 2022, the accumulated provisions for the external decommissioning trust funds were as follows:
| 2023 |  | 2022
| (in millions)
Alabama Power |  |  |
Plant Farley | $ | 1,259 |  |  | $ | 1,125 |
Georgia Power |  |  |
Plant Hatch | $ | 705 |  |  | $ | 628 |
Plant Vogtle Units 1 and 2 | 434 |  |  | 382 |
Plant Vogtle Units 3 and 4 | 24 |  |  | 8 |
Total | $ | 1,163 |  |  | $ | 1,018 |
Estimated costs of decommissioning | The estimated costs of decommissioning at December 31, 2023 based on the most current studies were as follows:
| Alabama Power |  | Georgia Power
| Plant Farley |  | Plant Hatch(*) |  | Plant Vogtle Units 1 and 2(*) |  | Plant Vogtle Unit 3(*)
Most current study year | 2023 |  | 2021 |  | 2021 |  | 2020
Decommissioning periods: |  |  |  |  |  |  |
Beginning year | 2037 |  | 2034 |  | 2047 |  | 2063
Completion year | 2087 |  | 2075 |  | 2079 |  | 2074
| (in millions)
Site study costs: |  |  |  |  |  |  |
Radiated structures | $ | 1,402 |  |  | $ | 771 |  |  | $ | 628 |  |  | $ | 284 |
Spent fuel management | 513 |  |  | 186 |  |  | 170 |  |  | 30 |
Non-radiated structures | 133 |  |  | 61 |  |  | 85 |  |  | 33 |
Total site study costs | $ | 2,048 |  |  | $ | 1,018 |  |  | $ | 883 |  |  | $ | 347 |
(*)Based on Georgia Power's ownership interests.

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- Definition Accumulated provisions for decommissioning. + References No definition available. + Details
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- Definition Tabular disclosure of assets measured at fair value measured on a recurring or nonrecurring basis. Includes, but is not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481850/410-20-50-1 + Details
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