Income Before Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Domestic	$ 7.9	$ 7.5	$ 0.9
Foreign	12.4	33.5	28.1
Income before income taxes	$ 20.3	$ 41.0	$ 29.0

Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

+ Details

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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

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