Financing (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended
	Jan. 31, 2014	Mar. 31, 2014
Credit arrangements by company
Expires, 2014		$ 523
Expires, 2015		95
Expires, 2016		480
Expires, 2018		4,130	[1]
Total		5,228
Unused		5,214
Executable Term-Loans, One Year		153
Executable Term-Loans, Two Years		40
Due Within One Year, Term Out		193
Due Within One Year, No Term Out		365
Southern Company [Member]
Credit arrangements by company
Expires, 2014		0	[1]
Expires, 2015		0	[1]
Expires, 2016		0	[1]
Expires, 2018		1,000	[1]
Total		1,000
Unused		1,000
Executable Term-Loans, One Year		0
Executable Term-Loans, Two Years		0
Due Within One Year, Term Out		0
Due Within One Year, No Term Out		0
Alabama Power [Member]
Credit arrangements by company
Expires, 2014		238	[1]
Expires, 2015		35	[1]
Expires, 2016		0	[1]
Expires, 2018		1,030	[1]
Total		1,303
Unused		1,303
Executable Term-Loans, One Year		53
Executable Term-Loans, Two Years		0
Due Within One Year, Term Out		53
Due Within One Year, No Term Out		185
Georgia Power [Member]
Credit arrangements by company
Expires, 2014		0	[1]
Expires, 2015		0	[1]
Expires, 2016		150	[1]
Expires, 2018		1,600	[1]
Total		1,750
Unused		1,736
Executable Term-Loans, One Year		0
Executable Term-Loans, Two Years		0
Due Within One Year, Term Out		0
Due Within One Year, No Term Out		0
Gulf Power [Member]
Credit arrangements by company
Expires, 2014		75	[1]
Expires, 2015		35	[1]
Expires, 2016		165	[1]
Expires, 2018		0	[1]
Total		275
Unused		275
Executable Term-Loans, One Year		50
Executable Term-Loans, Two Years		0
Due Within One Year, Term Out		50
Due Within One Year, No Term Out		60
Mississippi Power [Member]
Line of Credit Facility [Line Items]
Bank Loans Period Of Extension	18 months
Credit arrangements by company
Expires, 2014		135	[1]
Expires, 2015		0	[1]
Expires, 2016		165	[1]
Expires, 2018		0	[1]
Total		300
Unused		300
Executable Term-Loans, One Year		25
Executable Term-Loans, Two Years		40
Due Within One Year, Term Out		65
Due Within One Year, No Term Out		70
Debt Instrument, Description of Variable Rate Basis		P1M
Aggregate Principal Amount Of Floating Rate Bank Loan	250
Southern Power [Member]
Credit arrangements by company
Expires, 2014		0	[1]
Expires, 2015		0	[1]
Expires, 2016		0	[1]
Expires, 2018		500	[1]
Total		500
Unused		500
Executable Term-Loans, One Year		0
Executable Term-Loans, Two Years		0
Due Within One Year, Term Out		0
Due Within One Year, No Term Out		0
Other Subsidiaries [Member]
Credit arrangements by company
Expires, 2014		75	[1]
Expires, 2015		25	[1]
Expires, 2016		0	[1]
Expires, 2018		0	[1]
Total		100
Unused		100
Executable Term-Loans, One Year		25
Executable Term-Loans, Two Years		0
Due Within One Year, Term Out		25
Due Within One Year, No Term Out		$ 50

[1] No credit arrangements expire in 2017.