Segment Information - Reconciliation of Segments' Earnings from Operations to Company's Consolidated Earnings from Operations Before Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Segment Reporting [Abstract]
Earnings from operations for segments	$ 976.3	$ 921.1	$ 958.9
Unallocated corporate expenses	(181.8)	(161.9)	(152.1)
Interest expense, financing costs and other (income) expense, net	(34.0)	(44.6)	(50.2)
Other operating expense	0.0	(38.0)	(46.7)
Earnings from operations before income taxes	$ 760.5	$ 676.6	$ 709.9

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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