Selected Quarterly Data (Unaudited) (Summarized Data) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Jan. 31, 2015	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2017	Jan. 31, 2016	Dec. 31, 2014	Dec. 31, 2013
Accounts Receivable - trade		$ 261.3		$ 261.1	$ 252.4	$ 259.6				$ 261.3	$ 259.6
Inventories, net		1,381.4		1,386.9	1,293.5	1,295.3				1,381.4	1,295.3
Stockholders' equity	$ 2,601.1	2,221.1		2,223.0	2,230.4	2,202.5				2,221.1	2,202.5	$ 2,620.3	$ 2,798.7
Revenues	133.0	373.4	$ 389.0	378.9	352.8	358.2	$ 365.0	$ 412.7	$ 431.5	1,494.1	1,567.4	1,695.7
Cost of sales	95.6	281.4	289.0	286.4	269.3	284.1	279.1	315.3	323.9	1,126.1	1,202.4	1,194.9
Net earnings (loss)	$ 7.1	$ 17.9	$ 19.8	$ 8.0	$ 2.5	$ (10.3)	$ (400.8)	$ 7.4	$ 17.9	$ 48.2	$ (385.8)	$ 88.1
Basic net earnings per share	$ 0.14	$ 0.35	$ 0.38	$ 0.15	$ 0.05	$ (0.20)	$ (7.68)	$ 0.14	$ 0.34	$ 0.93	$ (7.39)	$ 1.69
Diluted net earnings per share	$ 0.14	$ 0.34	$ 0.38	$ 0.15	$ 0.05	$ (0.20)	$ (7.68)	$ 0.14	$ 0.34	$ 0.92	$ (7.39)	$ 1.68
Impairment charge							$ 640.2				$ 640.2
Goodwill impairment charge	$ 0.0						310.4			$ 0.0	310.4	$ 0.0
Intangible assets impairment							177.8				$ 177.8
Property and equipment impairment							$ 152.0
Non-recurring costs						$ 32.4
As Reported
Accounts Receivable - trade				$ 289.0	$ 267.8
Inventories, net				1,367.5	1,284.0
Stockholders' equity				2,228.3	2,234.0
Revenues				391.4	368.2
Cost of sales				296.3	278.7
Net earnings (loss)				$ 9.6	$ 6.2
Basic net earnings per share				$ 0.18	$ 0.12
Diluted net earnings per share				$ 0.18	$ 0.12
Adjustment | Revision of Claims Related to Contract Termination, Prior Period
Revenues					$ (12.1)
Cost of sales					(6.6)
Net earnings (loss)					$ (3.4)