Summary of Charges Related to Accrued Restructuring Activity (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Oct. 31, 2013	Jan. 31, 2014
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	$ 2.8	$ 2.8
Restructuring charge	0.3	0.6
Adjustments	(0.3)	(0.3)
Cash payments	(0.6)	(1.0)
Currency translation
Balance at end period	2.2	1.5
Employee Severance and Benefits
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	1.8	1.8
Restructuring charge	0.2
Adjustments	(0.2)	(0.2)
Cash payments	(0.5)	(0.6)
Currency translation
Balance at end period	1.3	0.5
Facility Exit Costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	0.2	0.2
Restructuring charge		0.6
Adjustments		(0.1)
Currency translation
Balance at end period	0.2	0.7
Aquisition Related Charges
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	0.8	0.8
Restructuring charge	0.1
Adjustments	(0.1)
Cash payments	(0.1)	(0.4)
Currency translation
Balance at end period	$ 0.7	$ 0.3