Financial Instruments and Risk Management (Impact of Cash Flow Hedges on Accumulated Other Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Reclassification of net losses to earnings, net of taxes of $1.0 and $2.1	$ 1.7	[1]	$ 3.9	$ 3.9
Treasury Locks [Member]
Net unamortized losses at beginning of year, net of taxes of $3.7 and $5.8	(6.8)		(10.7)
Reclassification of net losses to earnings, net of taxes of $1.0 and $2.1	1.7		3.9
Net unamortized losses at end of year, net of taxes of $2.7 and $3.7	(5.1)		(6.8)
Net unamortized losses at beginning of year, tax effect	3.7		5.8
Reclassification of net losses to earnings, tax effect	1.0		2.1
Net unamortized losses at end of year, tax effect	$ 2.7		$ 3.7

[1] Gross amount reclassified to interest expense, and related taxes reclassified to income taxes.