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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenues (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2021
Southern Company Gas |
Disaggregation of Revenue [Line Items] |
Period for collection of revenue prior to billings | 24 months

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- Definition Period For Collection Of Revenue Prior To Billing (WNAs) + 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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- Details
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Period Type: |