Retirement Benefits (Tables)

6 Months Ended

Jun. 30, 2011

Retirement Benefits [Abstract]

Pension Plans and Postretirement Plans

	Southern			Alabama			Georgia			Gulf			Mississippi
Pension Plans	Company			Power			Power			Power			Power
	(in millions)
Three Months Ended June 30, 2011
Service cost	$	46		$	10		$	15		$	2		$	2
Interest cost		97			24			36			5			5
Expected return on plan assets		(152	)		(43	)		(58	)		(7	)		(6	)
Net amortization		13			4			4			—			—
Net cost (income)	$	4		$	(5	)	$	(3	)	$	—		$	1
Six Months Ended June 30, 2011
Service cost	$	92		$	21		$	29		$	4		$	4
Interest cost		195			48			72			9			9
Expected return on plan assets		(304	)		(86	)		(117	)		(14	)		(12	)
Net amortization		26			7			9			1			1
Net cost (income)	$	9		$	(10	)	$	(7	)	$	—		$	2
Three Months Ended June 30, 2010
Service cost	$	43		$	11		$	13		$	2		$	2
Interest cost		97			24			37			4			5
Expected return on plan assets		(137	)		(42	)		(55	)		(6	)		(6	)
Net amortization		10			2			3			—			—
Net cost (income)	$	13		$	(5	)	$	(2	)	$	—		$	1
Six Months Ended June 30, 2010
Service cost	$	86		$	21		$	27		$	4		$	4
Interest cost		195			48			73			8			9
Expected return on plan assets		(275	)		(84	)		(110	)		(12	)		(11	)
Net amortization		21			5			7			1			1
Net cost (income)	$	27		$	(10	)	$	(3	)	$	1		$	3

	Southern			Alabama			Georgia			Gulf			Mississippi
Postretirement Benefits	Company			Power			Power			Power			Power
	(in millions)
Three Months Ended June 30, 2011
Service cost	$	5		$	2		$	2		$	1		$	1
Interest cost		23			6			10			1			1
Expected return on plan assets		(16	)		(7	)		(7	)		(1	)		(1	)
Net amortization		5			1			2			—			—
Net cost (income)	$	17		$	2		$	7		$	1		$	1
Six Months Ended June 30, 2011
Service cost	$	10		$	3		$	4		$	1		$	1
Interest cost		46			12			20			2			2
Expected return on plan assets		(32	)		(13	)		(15	)		(1	)		(1	)
Net amortization		10			3			5			—			—
Net cost (income)	$	34		$	5		$	14		$	2		$	2
Three Months Ended June 30, 2010
Service cost	$	7		$	1		$	2		$	1		$	1
Interest cost		25			7			11			1			1
Expected return on plan assets		(16	)		(6	)		(7	)		(1	)		(1	)
Net amortization		5			1			3			—			—
Net cost (income)	$	21		$	3		$	9		$	1		$	1
Six Months Ended June 30, 2010
Service cost	$	13		$	3		$	4		$	1		$	1
Interest cost		50			13			22			2			2
Expected return on plan assets		(32	)		(12	)		(15	)		(1	)		(1	)
Net amortization		10			3			6			—			—
Net cost (income)	$	41		$	7		$	17		$	2		$	2