CONSOLIDATED ENTITIES AND EQUITY METHOD INVESTMENTS - Southern Company (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Equity investments in unconsolidated subsidiaries	$ 1,443	$ 1,282
Southern Holdings Company
Schedule of Equity Method Investments [Line Items]
Equity investments in unconsolidated subsidiaries	$ 112	$ 101

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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