CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - 6 months ended Jul. 31, 2016 - USD ($) shares in Millions, $ in Millions	Total	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Non-controlling Interests [Member]
Beginning Balances at Jan. 31, 2016	$ 2,929.5	$ 2,012.5	$ (278.1)	$ 1.3	$ 1,175.7	$ 18.1
Beginning Balance, Shares at Jan. 31, 2016	126.8			126.8
Exercise of stock options and vesting of restricted stock units ("RSUs")	$ 8.3	0.0	0.0	$ 0.0	8.3	0.0
Exercise of stock options and vesting of restricted stock units ("RSUs"), shares				0.4
Tax effect of exercise of stock options and vesting of RSUs	(0.7)	0.0	0.0	$ 0.0	(0.7)	0.0
Share-based compensation expense	10.7	0.0	0.0	0.0	10.7	0.0
Purchase and retirement of Common Stock, Value	$ (149.9)	(131.8)	0.0	$ 0.0	(18.1)	0.0
Purchase and retirement of Common Stock, Shares	(2.3)			(2.3)
Cash dividends on Common Stock	$ (106.7)	(106.7)	0.0	$ 0.0	0.0	0.0
Other comprehensive earnings, net of tax	45.9	0.0	45.9	0.0	0.0	0.0
Net earnings	193.2	193.2	0.0	0.0	0.0	0.0
Non-controlling interests	(1.6)	0.0	0.0	0.0	0.0	(1.6)
Ending Balances at Jul. 31, 2016	$ 2,928.7	$ 1,967.2	$ (232.2)	$ 1.3	$ 1,175.9	$ 16.5
Ending Balance, Shares at Jul. 31, 2016	124.9			124.9