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REGULATORY MATTERS - GAS Schedule of Utility Regulation and Rate Design (Details) |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Nov. 16, 2023 | Aug. 28, 2023 | Nov. 30, 2021 | Dec. 31, 2023 | Dec. 31, 2021
Nicor Gas |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE | 9.51% |  | 9.75% | 9.51% |
Atlanta Gas Light |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE |  |  |  | 10.25% |
Virginia Natural Gas |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE |  | 9.70% |  | 9.70% | 9.50%
Chattanooga Gas |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE |  |  |  | 9.80% |

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- Definition Percentage of public utility's approved return on equity. + References No definition available. + Details
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