Quarterly Financial and Market Data (Unaudited) (Details) (USD $) In Millions, except Per Share data, 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
Quarterly Financial and Market Data (Unaudited)
Net sales	$ 426.8	$ 412.3	$ 422.6	$ 416.5	$ 387.3	$ 391.6	$ 399.2	$ 400.1	$ 1,678.2	$ 1,578.2	$ 1,392.4
Gross margin	113.1	112.1	116.8	112.0	95.6	99.2	105.5	106.4	454.0	406.7	342.1
Other income, net							(9.5)			(9.5)	(3.0)
Operating income	67.0	69.0	71.9	63.0	54.3	60.0	73.9	60.6	270.9	248.8	192.0
Net income	$ 47.1	$ 48.7	$ 48.5	$ 43.6	$ 36.9	$ 39.8	$ 48.0	$ 39.6
Net income per common share:
Basic	$ 0.47	$ 0.49	$ 0.49	$ 0.43	$ 0.37	$ 0.40	$ 0.48	$ 0.40	$ 1.88	$ 1.64	$ 1.37
Diluted	$ 0.46	$ 0.48	$ 0.48	$ 0.43	$ 0.36	$ 0.39	$ 0.47	$ 0.39	$ 1.84	$ 1.61	$ 1.35
Maximum
Market price:
Common Stock Value during the Period	$ 44.69	$ 39.67	$ 35.46	$ 30.23	$ 27.29	$ 26.49	$ 27.80	$ 26.71
Minimum
Market price:
Common Stock Value during the Period	$ 38.09	$ 33.88	$ 27.64	$ 26.50	$ 23.55	$ 22.53	$ 23.05	$ 23.42