Regulatory Matters - GPC Rate Plans (Details) $ in Millions									1 Months Ended		9 Months Ended
	Sep. 17, 2025 MW	Sep. 04, 2025 MW	Jul. 30, 2025 project MW unit	Jul. 15, 2025 USD ($) MW facility	Jul. 08, 2025 MW	Jul. 01, 2025	May 14, 2025 USD ($)	Apr. 01, 2025 USD ($)	Jul. 31, 2025 project MW	Jul. 30, 2025 USD ($) MW	Sep. 30, 2025 USD ($)
GEORGIA POWER CO
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)		200							1,100
Approximate nameplate capacity			260							260
Requested rate increase amount | $										$ 16,700
Capital costs | $											$ 1,500
GEORGIA POWER CO | 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 | 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 | Affiliate PPA
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)									50
Approved capacity increase (in MWs)									750
GEORGIA POWER CO | 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 | 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 | 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 | 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 | July 2025 Requested For Certification
Public Utilities, General Disclosures [Line Items]
Capital costs | $											$ 725
GEORGIA POWER CO | SEGCO
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)				500
Ownership percentage, equity method investment				50.00%
GEORGIA POWER CO | 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 | Plant Bowen Units 1 Through 4
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)				3,160
GEORGIA POWER CO | 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 | 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 | 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 | 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 | Plant Scherer Unit 3
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)									187
GEORGIA POWER CO | 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 | Maximum
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)	8,500
Approved rate increase (decrease) | $							$ 200
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
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 | Minimum
Public Utilities, General Disclosures [Line Items]
Retail rate of return on common equity						9.50%
GEORGIA POWER CO | 2022 Alternate Rate Plan | 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 | Affiliate PPA
Public Utilities, General Disclosures [Line Items]
Requested additional generating capacity (in MWs)					50
Approved capacity increase (in MWs)					750