CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Income Statement [Abstract]
Net sales	$ 1,012.4	$ 976.2	$ 3,121.5	$ 2,835.4
Cost of sales	383.1	376.2	1,152.5	1,076.8
Gross profit	629.3	600.0	1,969.0	1,758.6
Selling, general and administrative expenses	502.9	436.0	1,447.1	1,260.3
Earnings from operations	126.4	164.0	521.9	498.3
Interest expense and financing costs	10.1	10.8	29.7	31.9
Other expense, net	1.8	2.8	5.1	7.3
Earnings from operations before income taxes	114.5	150.4	487.1	459.1
Provision for income taxes	19.6	50.2	105.2	150.9
Net earnings	$ 94.9	$ 100.2	$ 381.9	$ 308.2
Net earnings per share:
Basic (in dollars per share)	$ 0.78	$ 0.81	$ 3.10	$ 2.47
Diluted (in dollars per share)	$ 0.77	$ 0.80	$ 3.08	$ 2.46
Weighted-average number of common shares:
Basic (in shares)	122.3	124.4	123.3	124.5
Diluted (in shares)	123.1	125.0	124.0	125.1