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ACQUISITIONS AND DISPOSITIONS - GAS Acquisitions and Dispositions Narrative (Details) - Southern Company Gas $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jul. 31, 2021 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Sep. 30, 2022 USD ($) storageFacility
Business Acquisition [Line Items] |  |  |  |  |  |
Gain (loss) on dispositions |  |  | $ 7 | $ 4 | $ 127 |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Sequent |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Consideration for sale | $ 159 |  |  |  |  |
Gain (loss) on dispositions | 121 |  | 121 |  | 121 |
Gain (loss) on dispositions, after tax | 92 |  | 92 |  | 92 |
Deferred tax expense, increase from change in appointment rate | $ 85 |  | $ 85 |  | $ 85 |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Natural Gas Storage Facilities |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Consideration for sale |  |  |  |  |  | $ 186
Gain (loss) on dispositions |  | $ (131) |  |  |  |
Gain (loss) on dispositions, after tax |  | $ (99) |  |  |  |
Number of natural gas storage facilities sold | storageFacility |  |  |  |  |  | 2

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