Retirement Benefits (Tables)

9 Months Ended

Sep. 30, 2012

Compensation and Retirement Disclosure [Abstract]

Pension Plans and Postretirement Plans

Components of the net periodic benefit costs for the three and nine months ended September 30, 2012 and 2011 were as follows:

Pension Plans	Southern Company			Alabama Power			Georgia Power			Gulf Power			Mississippi   Power
	(in millions)
Three Months Ended September 30, 2012
Service cost	$	49		$	11		$	15		$	2		$	2
Interest cost	98			23			35			5			5
Expected return on plan assets	(145		)	(40		)	(56		)	(7		)	(6		)
Net amortization	32			8			12			1			2
Net cost	$	34		$	2		$	6		$	1		$	3
Nine Months Ended September 30, 2012
Service cost	$	148		$	33		$	45		$	7		$	7
Interest cost	295			70			106			13			14
Expected return on plan assets	(436		)	(121		)	(166		)	(20		)	(18		)
Net amortization	94			23			34			4			4
Net cost	$	101		$	5		$	19		$	4		$	7
Three Months Ended September 30, 2011
Service cost	$	46		$	11		$	14		$	2		$	3
Interest cost	97			24			36			4			4
Expected return on plan assets	(152		)	(44		)	(59		)	(6		)	(7		)
Net amortization	14			3			5			—			1
Net cost (income)	$	5		$	(6	)	$	(4	)	$	—		$	1
Nine Months Ended September 30, 2011
Service cost	$	138		$	32		$	43		$	6		$	7
Interest cost	292			72			108			13			13
Expected return on plan assets	(456		)	(130		)	(176		)	(20		)	(19		)
Net amortization	40			10			14			1			2
Net cost (income)	$	14		$	(16	)	$	(11	)	$	—		$	3

Postretirement Benefits	Southern Company			Alabama Power			Georgia Power			Gulf Power			Mississippi Power
	(in millions)
Three Months Ended September 30, 2012
Service cost	$	5		$	1		$	2		$	—		$	—
Interest cost	21			6			8			1			1
Expected return on plan assets	(15		)	(6		)	(7		)	—			—
Net amortization	5			1			3			—			—
Net cost	$	16		$	2		$	6		$	1		$	1
Nine Months Ended September 30, 2012
Service cost	$	16		$	4		$	5		$	1		$	1
Interest cost	63			17			27			3			3
Expected return on plan assets	(45		)	(18		)	(21		)	(1		)	(1		)
Net amortization	15			4			8			—			—
Net cost	$	49		$	7		$	19		$	3		$	3
Three Months Ended September 30, 2011
Service cost	$	6		$	1		$	1		$	—		$	—
Interest cost	23			6			11			1			1
Expected return on plan assets	(16		)	(6		)	(8		)	—			—
Net amortization	5			2			3			—			—
Net cost	$	18		$	3		$	7		$	1		$	1
Nine Months Ended September 30, 2011
Service cost	$	16		$	4		$	5		$	1		$	1
Interest cost	69			18			31			3			3
Expected return on plan assets	(48		)	(19		)	(23		)	(1		)	(1		)
Net amortization	15			5			8			—			—
Net cost	$	52		$	8		$	21		$	3		$	3