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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration of Revenue (Narrative) (Details) - Mississippi Power | 12 Months Ended
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Dec. 31, 2021
Concentration Risk [Line Items] |
Wholesale customers representing total operating revenues | 14.30%
Period of cancellation notices | 10 years

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- Definition Percentage Of Wholesale Customers To Operating Revenue + References No definition available. + Details
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- Definition Period Of Contract Cancellation Notices Of Wholesale Customers + 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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