Foreign Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Foreign operations data
Revenues	$ 356.6	$ 353.2	$ 338.9	$ 272.3	$ 331.7	$ 331.9	$ 323.1	$ 256.5	$ 1,321.0	$ 1,243.2	$ 1,191.4
Identifiable assets	6,549.6				6,055.4				6,549.6	6,055.4	5,857.5
Foreign Operations (Textual) [Abstract]
Maximum percentage of consolidated revenues derive from any individual foreign country									10.00%
Percentage of company's identifiable assets	10.00%								10.00%
Foreign [Member]
Foreign operations data
Revenues									332.1	279.8	278.6
Identifiable assets	2,200.1				1,897.9				2,200.1	1,897.9	1,766.6
United States [Member]
Foreign operations data
Revenues									988.9	963.4	912.8
Identifiable assets	$ 4,349.5				$ 4,157.5				$ 4,349.5	$ 4,157.5	$ 4,090.9