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FINANCING - Outstanding Classes of Capital Stock Narrative (Details) shares in Millions, $ in Millions | 12 Months Ended
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Dec. 31, 2021 USD ($) shares
Debt Instrument [Line Items] |
Stock issued employee and director stock plans (in shares) | 3.5
Proceeds from issuance of shares under share-based compensation plans | $ | $ 73
Number of shares reserved for issuance to stock-based compensation plan (in shares) | 127.0
Southern Company Common Stock |
Debt Instrument [Line Items] |
Remaining shares available for awards (in shares) | 31.5

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- Definition Share based compensation arrangement by share based payment award number of shares reserved for issuance pursuant to stock based compensation plan. + References No definition available. + Details
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- Definition Stock issued during period shares company investment plan and employee and director stock plans. + References No definition available. + Details
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- Definition Amount of cash inflow from issuance of shares under share-based payment arrangement. Includes, but is not limited to, option exercised. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120381028&loc=SL79508275-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Details
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