CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 586.4	$ 370.1	$ 446.1
Other comprehensive (loss) earnings, net of tax
Foreign currency translation adjustments	(60.2)	95.7	(8.4)
Unrealized (loss) gain on marketable securities	0.0	(2.6)	1.8
Unrealized (loss) gain on hedging instruments	(1.6)	(6.8)	10.7
Unrealized (loss) gain on benefit plans	(6.8)	31.9	17.8
Total other comprehensive (loss) earnings, net of tax	(68.6)	118.2	21.9
Comprehensive earnings	$ 517.8	$ 488.3	$ 468.0

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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