Employee Benefits (Components Of Estimated Pension And Postretirement Benefits Expense) (Details) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Pension Expense [Member]
Service cost	$ 21.5	$ 20.1	$ 42.8	$ 40.2
Interest cost	48.9	45.9	97.0	91.9
Expected return on assets	(67.3)	(64.4)	(134.4)	(128.9)
Amortization, net	12.8	6.4	25.0	12.7
Net periodic benefit expense (benefit)	15.9	8.0	30.4	15.9
Postretirement Benefits Expense[Member]
Service cost	2.3	3.0	4.6	6.1
Interest cost	6.2	7.1	12.4	14.2
Expected return on assets	(3.8)	(3.9)	(7.6)	(7.8)
Amortization, net	(1.3)	(2.3)	(2.5)	(4.7)
Net periodic benefit expense (benefit)	$ 3.4	$ 3.9	$ 6.9	$ 7.8