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Acquisitions and Dispositions - Schedule of Construction Projects (Details) - SOUTHERN POWER CO - MW	3 Months Ended
	Mar. 31, 2026	Feb. 28, 2026
Millers Branch Solar Development Phase 1
Business Combination [Line Items]
Life output of plant (in years)	20 years
Nameplate capacity placed in service		200
Millers Branch Solar Development Phase 2
Business Combination [Line Items]
Approximate nameplate capacity	180
Life output of plant (in years)	15 years
Millers Branch Solar Development Phase 3
Business Combination [Line Items]
Approximate nameplate capacity	132
Life output of plant (in years)	15 years

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