Pension and Other Postretirement Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2011

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Components of Net Periodic Benefit Expense

	Pension		Other Postretirement
Components of Net Periodic Benefit Expense	2011	2010	2011	2010
Millions
For the Quarter Ended June 30,
Service Cost	$1.9	$1.6	$0.9	$1.2
Interest Cost	6.8	6.5	2.7	2.8
Expected Return on Plan Assets	(8.6)	(8.4)	(2.5)	(2.4)
Amortization of Prior Service Costs	0.1	0.1	(0.5)	-
Amortization of Net Loss	3.0	1.7	2.2	1.2
Amortization of Transition Obligation	-	-	0.1	0.6
Net Periodic Benefit Expense	$3.2	$1.5	$2.9	$3.4
For the Six Months Ended June 30,
Service Cost	$3.8	$3.1	$1.9	$2.4
Interest Cost	13.7	13.1	5.4	5.5
Expected Return on Plan Assets	(17.3)	(16.8)	(4.9)	(4.8)
Amortization of Prior Service Costs	0.2	0.2	(0.9)	-
Amortization of Net Loss	6.0	3.3	4.3	2.4
Amortization of Transition Obligation	-	-	0.1	1.2
Net Periodic Benefit Expense	$6.4	$2.9	$5.9	$6.7