Segments Information Regarding Operations by Geographic Area (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 30, 2015	Apr. 30, 2014
Segment Reporting Information [Line Items]
Net revenue	$ 646.5	$ 592.5
Other Asia Pacific
Segment Reporting Information [Line Items]
Net revenue	92.0	74.7
Americas
Segment Reporting Information [Line Items]
Net revenue	244.0	205.7
Americas | U.S.
Segment Reporting Information [Line Items]
Net revenue	199.6	169.5
Americas | Other Americas
Segment Reporting Information [Line Items]
Net revenue	44.4	36.2
Europe, Middle East and Africa
Segment Reporting Information [Line Items]
Net revenue	245.4	225.5
Asia Pacific
Segment Reporting Information [Line Items]
Net revenue	157.1	161.3
Asia Pacific | Japan
Segment Reporting Information [Line Items]
Net revenue	$ 65.1	$ 86.6