| **BUSINESS SEGMENT INFORMATION (Policies)** | 6 Months Ended                                                                           |
|---------------------------------------------|------------------------------------------------------------------------------------------|
||
| **BUSINESS SEGMENTS [Abstract]**            | Â                                                                                        |
| Intersegment elimination                    | Intersegment revenues are eliminated in the Condensed Consolidated Financial Statements. |

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| - Details**Name:**gas_BusinessSegmentsAbstract**Namespace Prefix:**gas**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
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| - Definition
Disclosure of accounting policy for subsidiaries or other investments that are consolidated, including the accounting treatment for intercompany accounts or transactions and any noncontrolling interest.
+ References
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