Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Selected Quarterly Financial Information [Abstract]
Net Sales	$ 1,231.6	$ 1,279.8	$ 1,267.9	$ 1,185.8	$ 1,088.5	$ 1,132.8	$ 1,121.5	$ 1,047.7	$ 4,965.1	$ 4,390.5	$ 3,962.0
Gross Profit	587.8	615.8	617.7	577.6	531.2	555.9	558.5	518.0	2,398.9	2,163.6	1,964.8
Pre-tax Earnings	229.8	259.4	265.9	231.9	200.8	226.0	235.4	210.9	987.0	873.1	789.7
Net Earnings	$ 168.8	$ 197.6	$ 211.2	$ 174.3	$ 152.4	$ 143.1	$ 148.9	$ 134.2	$ 751.9	$ 578.6	$ 499.4
Basic Net Earnings per Share (in dollars per share)	$ 0.59	$ 0.69	$ 0.74	$ 0.61	$ 0.53	$ 0.50	$ 0.52	$ 0.46	$ 2.62	$ 2.01	$ 1.73
Diluted Net Earnings per Share (in dollars per share)	$ 0.59	$ 0.69	$ 0.74	$ 0.61	$ 0.53	$ 0.50	$ 0.52	$ 0.46	$ 2.62	$ 2.01	$ 1.73
Net earnings, absent impact of tax act	$ 145.2	$ 164.3	$ 168.7	$ 147.0	$ 128.1				$ 625.2	$ 554.2
Basic net earnings per share, absent impact of tax act (in dollars per share)	$ 0.51	$ 0.57	$ 0.59	$ 0.51	$ 0.45				$ 2.18	$ 1.92
Diluted net earnings per share, absent impact of tax act (in dollars per share)	$ 0.51	$ 0.57	$ 0.59	$ 0.51	$ 0.45				$ 2.18	$ 1.92