Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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No definition available.

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Derivative Instruments - Additional Information (Detail) - Forward Contracts - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017	Jul. 31, 2017
Derivative [Line Items]
Notional amount of cash flow hedge instruments	$ 12.1		$ 12.1		$ 10.9
Unrealized gain on cash flow hedges	0.1		0.1		0.5
Other Income (Expense), Net
Derivative [Line Items]
Realized gains (losses) on cash flow hedge instruments	0.1	$ (0.2)	0.4	$ (0.5)
Designated as Hedging Instrument
Derivative [Line Items]
Derivative liabilities, current	$ 0.1		$ 0.1
Derivative asset, current					$ 0.6