Condensed Consolidated Balance Sheets (Unaudited) - Southern (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Other intangible assets, amortization	$ 457	$ 444

Amount of accumulated amortization of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482558/350-40-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 10
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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Period Type:	instant