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- Definition

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- Definition

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of property, plant, and equipment acquired in business combination and recognized at acquisition date.

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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The proportionate share of interest (percent) in a jointly owned utility plant.

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Acquisitions and Dispositions - Narrative (Details) $ in Millions	Jul. 30, 2025 USD ($)	Jun. 06, 2025 USD ($)	Sep. 30, 2025 USD ($) MW	Jun. 19, 2025
MISSISSIPPI POWER CO \| Plant Daniel Units 1 and 2
Business Combination [Line Items]
Proportionate ownership share				50.00%
Proceeds from acquisition \| $	$ 36
ALABAMA POWER CO \| Tenaska Alabama Partners, L.P.
Business Combination [Line Items]
Purchase price \| $		$ 635
Assets recorded in PPE \| $		$ 622
Approximate nameplate capacity \| MW			855
Millers Branch Solar Development Phase 1 \| SOUTHERN POWER CO
Business Combination [Line Items]
Approximate nameplate capacity \| MW			200
Millers Branch Solar Development Phase 2 \| SOUTHERN POWER CO
Business Combination [Line Items]
Approximate nameplate capacity \| MW			180
Millers Branch Solar Development Phase 3 \| SOUTHERN POWER CO
Business Combination [Line Items]
Approximate nameplate capacity \| MW			132
Millers Branch Solar Development \| SOUTHERN POWER CO
Business Combination [Line Items]
Approximate nameplate capacity \| MW			512
Construction work in progress \| $			$ 661
Wind Facilities \| SOUTHERN POWER CO
Business Combination [Line Items]
Construction work in progress \| $			$ 165