Financial Instruments (Derivative Narrative) (Details) - USD ($) $ in Millions	Apr. 30, 2020	Jan. 31, 2020
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net gain expected to be recognized in next 24 months	$ 12.4
Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	889.3	$ 981.3
Derivatives not designated as hedging instruments \| Foreign currency contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 219.1	$ 736.2

Nominal or face amount used to calculate payment on derivative.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant