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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Quarterly Financial and Market Data (Unaudited)
Net sales	$ 387.3	$ 391.6	$ 399.2	$ 400.1	$ 355.3	$ 351.8	$ 353.7	$ 331.6	$ 1,578.2	$ 1,392.4	$ 1,173.6
Gross margin	95.6	99.2	105.5	106.4	85.6	86.5	87.0	83.0	406.7	342.1	282.6
Other (income) expense, net			(9.5)			2.7		(5.7)	(9.5)	(3.0)	3.5
Operating income	54.3	60.0	73.9	60.6	49.4	46.0	49.4	47.2	248.8	192.0	129.8
Net income	$ 36.9	$ 39.8	$ 48.0	$ 39.6	$ 39.5	$ 32.2	$ 37.4	$ 26.4
Net income per common share:
Basic	$ 0.37	$ 0.40	$ 0.48	$ 0.40	$ 0.40	$ 0.33	$ 0.38	$ 0.27	$ 1.64	$ 1.37	$ 0.79
Diluted	$ 0.36	$ 0.39	$ 0.47	$ 0.39	$ 0.39	$ 0.32	$ 0.37	$ 0.26	$ 1.61	$ 1.35	$ 0.77
Market price:
High (in dollars per share)	$ 27.29	$ 26.49	$ 27.80	$ 26.71	$ 25.84	$ 24.23	$ 21.90	$ 20.69
Low (in dollars per share)	$ 23.55	$ 22.53	$ 23.05	$ 23.42	$ 21.34	$ 18.07	$ 18.78	$ 17.58