Employee Benefits Plan (Tables)

9 Months Ended

Sep. 30, 2011

Notes To Financial Statements [Abstract]

Schedule of Defined Benefit Plans Disclosures [Text Block]

Following are the combined cost components of our two defined benefit pension plans for the periods indicated:

	Three months ended September 30,			Nine months ended September 30,
In millions	2011	2010	2011		2010
Service cost	$3	$3	$10		$8
Interest cost	7	7	21		21
Expected return on plan assets	(7)	(7)	(23)		(22)
Amortization of prior service cost	(1)	(1)	(2)		(2)
Recognized actuarial loss	3	3	10		8
Net pension benefit cost	$5	$5	$16		$13

Schedule of Costs of Retirement Plans [Text Block]

Following are the cost components of the AGL Postretirement Plan for the periods indicated:

	Three months ended September 30,		Nine months ended September 30,
In millions	2011	2010	2011	2010
Service cost	$1	$0	$1	$1
Interest cost	1	1	4	4
Expected return on plan assets	(1)	(1)	(4)	(4)
Amortization of prior service cost	(1)	(1)	(3)	(3)
Recognized actuarial loss	0	1	1	2
Net pension benefit cost	$0	$0	$(1)	$0