Segments Information Regarding Operations by Geographic Area (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014	Jul. 31, 2013
Segment Reporting Information [Line Items]
Net revenue	$ 637.1	$ 561.7	$ 1,229.6	$ 1,132.1
Other Asia Pacific
Segment Reporting Information [Line Items]
Net revenue			174.5	164.6
Americas
Segment Reporting Information [Line Items]
Net revenue	223.3	201.6	429.0	403.8
Americas | U.S.
Segment Reporting Information [Line Items]
Net revenue	184.6	164.6	354.1	331.0
Americas | Other Americas
Segment Reporting Information [Line Items]
Net revenue	38.7	37.0	74.9	72.8
Europe, Middle East and Africa
Segment Reporting Information [Line Items]
Net revenue	243.5	201.8	469.0	418.0
Asia Pacific
Segment Reporting Information [Line Items]
Net revenue	170.3	158.3	331.6	310.3
Asia Pacific | Japan
Segment Reporting Information [Line Items]
Net revenue	70.5	68.9	157.1	145.7
Asia Pacific | Other Asia Pacific
Segment Reporting Information [Line Items]
Net revenue	$ 99.8	$ 89.4