CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Unaudited) - USD ($) $ in Millions	3 Months Ended
Apr. 30, 2018	Apr. 30, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 142.3	$ 92.9
Other comprehensive (loss) earnings, net of tax
Foreign currency translation adjustments	(25.0)	12.1
Unrealized gain on marketable securities	0.0	0.1
Unrealized loss on hedging instruments	(7.3)	(1.0)
Unrealized gain on benefit plans	2.4	2.2
Other comprehensive (loss) earnings, net of tax	(29.9)	13.4
Comprehensive earnings	$ 112.4	$ 106.3

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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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