Acquisitions and Dispositions - Southern Power (Details) - SOUTHERN POWER CO $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($) MW
Millers Branch Solar Development
Business Acquisition [Line Items]
Approximate nameplate capacity	200
Ownership percentage by parent	100.00%
Life output of plant (in years)	20 years
South Cheyenne Solar Facility
Business Acquisition [Line Items]
Approximate nameplate capacity	150
Ownership percentage by parent	10000.00%
Life output of plant (in years)	20 years
South Cheyenne Solar Facility and Millers Branch Solar Development
Business Acquisition [Line Items]
Payments to Acquire Businesses and Interest in Affiliates \| $	$ 193
Maximum \| Millers Branch Solar Development
Business Acquisition [Line Items]
Approximate nameplate capacity	300

Approximate Nameplate Capacity

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The contracted life output of the plant.

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash outflow associated with the acquisition of a controlling interest in another entity or an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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