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Regulatory Matters - GPC Rate Plans (Details) $ in Millions								1 Months Ended
	Jul. 30, 2025 MW project unit	Jul. 15, 2025 USD ($) MW facility	Jul. 08, 2025 MW	Jul. 01, 2025	Jun. 20, 2025 MW	May 14, 2025 USD ($)	Apr. 01, 2025 USD ($)	Jul. 31, 2025 project MW	Jul. 30, 2025 USD ($) MW
GEORGIA POWER CO
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)					200
GEORGIA POWER CO | Maximum
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) | $						$ 200
GEORGIA POWER CO | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)								1,100
Approximate nameplate capacity	260								260
Requested rate increase amount | $									$ 16,700
GEORGIA POWER CO | Subsequent Event | First PPA
Public Utilities, General Disclosures [Line Items]
Approved capacity increase (in MWs)								930
Life output of plant (in years)								20 years
GEORGIA POWER CO | Subsequent Event | Second PPA
Public Utilities, General Disclosures [Line Items]
Approved capacity increase (in MWs)								646
Number of PPAs | project								5
Life output of plant (in years)								25 years
GEORGIA POWER CO | Subsequent Event | Affiliate PPA
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)								50
Approved capacity increase (in MWs)								750
GEORGIA POWER CO | Subsequent Event | Project Group 1
Public Utilities, General Disclosures [Line Items]
Number of PPAs | project	4
Public Utilities, Additional Generating Capacity To be Certified	1,195
GEORGIA POWER CO | Subsequent Event | project Group 2
Public Utilities, General Disclosures [Line Items]
Number of projects | project	3
Number of units | unit	5
Public Utilities, Additional Generating Capacity To be Certified	3,692
GEORGIA POWER CO | Subsequent Event | Project Group 3
Public Utilities, General Disclosures [Line Items]
Number of projects | project	9
Public Utilities, Additional Generating Capacity To be Certified	2,762
GEORGIA POWER CO | Subsequent Event | Fourth Project Group
Public Utilities, General Disclosures [Line Items]
Number of projects | project	2
Public Utilities, Additional Generating Capacity To be Certified	350
GEORGIA POWER CO | Subsequent Event | SEGCO
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		500
Ownership percentage, equity method investment		50.00%
GEORGIA POWER CO | Subsequent Event | Plant Scherer Unit Three
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		614
Proportionate ownership share		75.00%
GEORGIA POWER CO | Subsequent Event | Plant Bowen Units 1 Through 4
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		3,160
GEORGIA POWER CO | Subsequent Event | Plant Scherer Coal Units One and Two
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		137
Proportionate ownership share		8.40%
GEORGIA POWER CO | Subsequent Event | Plant McIntosh Units 10 And 11
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		1,319
Additional capacity		194
GEORGIA POWER CO | Subsequent Event | Plant McIntosh Units 1 Through 8
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		640
Additional capacity		74
GEORGIA POWER CO | Subsequent Event | Plant Vogtle Nuclear Units One and Two
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		1,060
Proportionate ownership share		45.70%
Additional capacity		54
GEORGIA POWER CO | Subsequent Event | Plant Scherer Unit 3
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)								187
GEORGIA POWER CO | Subsequent Event | Hydro Operations
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) | $		$ 25
Number of facilities | facility		4
Number of additional facilities | facility		2
GEORGIA POWER CO | Subsequent Event | Maximum
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)	8,500
Number of projects | project	18
Number of affiliate PPAs | project	2
Public Utilities, Additional Generating Capacity To be Certified	7,999
GEORGIA POWER CO | 2022 Alternate Rate Plan | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Retail rate of return on common equity				10.50%
Equity rate of return on common equity				56.00%
Portion of actual earnings above approved ROE applied to regulatory assets				40.00%
Portion of actual earnings above approved ROE band refunded to customers				40.00%
Portion of actual earnings above approved ROE band retained by subsidiary company				20.00%
GEORGIA POWER CO | 2022 Alternate Rate Plan | Subsequent Event | Minimum
Public Utilities, General Disclosures [Line Items]
Retail rate of return on common equity				9.50%
GEORGIA POWER CO | 2022 Alternate Rate Plan | Subsequent Event | Maximum
Public Utilities, General Disclosures [Line Items]
Retail rate of return on common equity				11.90%
MISSISSIPPI POWER CO
Public Utilities, General Disclosures [Line Items]
Approved rate increase (decrease) | $							$ 8
MISSISSIPPI POWER CO | Subsequent Event | Affiliate PPA
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)			50
Approved capacity increase (in MWs)			750

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