Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Income Taxes [Line Items]
U.S. Federal statutory tax rate	35.00%	35.00%	35.00%
Discrete tax benefit	$ 12.9
Reduction of taxes from change in classification of Canadian operations	8.8
Discrete tax items, deduction for historical currency losses	2.7
Remeasurement of tax reserves on a reduction in uncertain federal tax credits for R&D	1.0	0.5
Other items	0.4
Discrete tax items, reversal of tax reserves as a result of the expiration of applicable statutes of limitations including interest		0.6
Undistributed earnings of consolidated foreign subsidiaries	66
Unrecognized tax benefits	6.9	7.3	6.8
Unrecognized tax benefits that would impact effective tax rate	5.2
Unrecognized tax benefits, interest on income taxes expense	2.8
Reduction in uncertain tax benefits and accrued interest	1.9
Unrecognized tax benefits, accrued interest and penalties	0.6	0.7
Deferred tax assets	9.3	6.8
Refundable income tax assets	9.3	1.0
BELGIUM
Income Taxes [Line Items]
Net operating loss carryforwards, not subject to expiration	3.7
ITALY
Income Taxes [Line Items]
Net operating loss carryforwards, subject to expiration	0.1
Net operating loss carryforwards, expiration year	2017
UNITED KINGDOM
Income Taxes [Line Items]
Net operating loss carryforwards, not subject to expiration	3.2
DENMARK
Income Taxes [Line Items]
Net operating loss carryforwards, not subject to expiration	0.1
CANADA
Income Taxes [Line Items]
Net operating loss carryforwards, subject to expiration	1.3
Net operating loss carryforwards, expiration year	2024
UNITED STATES
Income Taxes [Line Items]
Net operating loss carryforwards, subject to expiration	0.2
Net operating loss carryforwards, expiration year	2034
FRANCE
Income Taxes [Line Items]
Net operating loss carryforwards, not subject to expiration	1.0
State and Local Jurisdiction
Income Taxes [Line Items]
State tax credit carryforwards	$ 9.6
State tax credit carryforwards, expiration year	2029