CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (USD $) In Millions, unless otherwise specified	3 Months Ended
Apr. 30, 2015	Apr. 30, 2014
Statement of Comprehensive Income [Abstract]
Net earnings	$ 104.9us-gaap_NetIncomeLoss	$ 125.6us-gaap_NetIncomeLoss
Other comprehensive earnings (loss), net of tax
Foreign currency translation adjustments	3.6	17.2
Unrealized gain on marketable securities	1.1	0.8
Unrealized loss on hedging instruments	(4.4)	(3.5)
Net unrealized gain on benefit plans	4.7	2.0
Other comprehensive earnings, net of tax	5.0	16.5
Comprehensive earnings	$ 109.9us-gaap_ComprehensiveIncomeNetOfTax	$ 142.1us-gaap_ComprehensiveIncomeNetOfTax

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Comprehensive Income

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-Name Accounting Standards Codification

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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 adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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