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REGULATORY MATTERS - GAS Schedule of Utility Regulation and Rate Design (Details) |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Nov. 18, 2021 | Sep. 14, 2021 | Dec. 31, 2019 | Dec. 31, 2021 | Dec. 31, 2019
Nicor Gas |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE | 9.75% |  |  | 9.75% | 9.73%
Atlanta Gas Light |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE |  |  | 10.25% | 10.25% |
Virginia Natural Gas |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |
Authorized ROE |  | 9.50% |  | 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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