Retirement Benefit Plans - Balance Sheet (Details) - USD ($) $ in Millions	Jan. 31, 2017	Jan. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Amounts Recognized in Balance Sheet	$ 75.9	$ 76.0
Other long-term liabilities
Defined Benefit Plan Disclosure [Line Items]
Amounts Recognized in Balance Sheet	39.0	43.8
Accumulated other comprehensive loss
Defined Benefit Plan Disclosure [Line Items]
Amounts Recognized in Balance Sheet	$ 36.9	$ 32.2

The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant